diff --git a/caps/nsIScriptSecurityManager.idl b/caps/nsIScriptSecurityManager.idl
index ad482859df80..2cfb7b327165 100644
--- a/caps/nsIScriptSecurityManager.idl
+++ b/caps/nsIScriptSecurityManager.idl
@@ -231,14 +231,15 @@ interface nsIScriptSecurityManager : nsISupports
     nsIPrincipal getChannelResultStoragePrincipal(in nsIChannel aChannel);
 
     /**
-     * This method does getChannelResultPrincipal() +
-     * getChannelResultStoragePrincipal().
-     * This method is mainly done for Document::Reset(). There are no other
-     * reasons to use this method.
+     * This method returns 2 principals from a nsIChannel:
+     * - aPrincipal is the regular principal.
+     * - aPartitionedPrincipal is aPrincipal plus an isolation key in its
+     *   originAttributes.
+     * See more in StoragePrincipalHelper.h
      */
     void getChannelResultPrincipals(in nsIChannel aChannel,
                                     out nsIPrincipal aPrincipal,
-                                    out nsIPrincipal aStoragePrincipal);
+                                    out nsIPrincipal aPartitionedPrincipal);
 
     /**
      * Temporary API until bug 1220687 is fixed.
diff --git a/caps/nsScriptSecurityManager.cpp b/caps/nsScriptSecurityManager.cpp
index b179e572ed67..124a92c08806 100644
--- a/caps/nsScriptSecurityManager.cpp
+++ b/caps/nsScriptSecurityManager.cpp
@@ -251,13 +251,14 @@ nsScriptSecurityManager::GetChannelResultStoragePrincipal(
     return rv;
   }
 
-  return StoragePrincipalHelper::Create(aChannel, principal, aPrincipal);
+  return StoragePrincipalHelper::Create(
+      aChannel, principal, /* aForceIsolation */ false, aPrincipal);
 }
 
 NS_IMETHODIMP
 nsScriptSecurityManager::GetChannelResultPrincipals(
     nsIChannel* aChannel, nsIPrincipal** aPrincipal,
-    nsIPrincipal** aStoragePrincipal) {
+    nsIPrincipal** aPartitionedPrincipal) {
   nsresult rv = GetChannelResultPrincipal(aChannel, aPrincipal,
                                           /*aIgnoreSandboxing*/ false);
   if (NS_WARN_IF(NS_FAILED(rv))) {
@@ -269,12 +270,12 @@ nsScriptSecurityManager::GetChannelResultPrincipals(
     // principal for the storage principal too, since attempting to create a
     // storage principal would fail anyway.
     nsCOMPtr<nsIPrincipal> copy = *aPrincipal;
-    copy.forget(aStoragePrincipal);
+    copy.forget(aPartitionedPrincipal);
     return NS_OK;
   }
 
-  return StoragePrincipalHelper::Create(aChannel, *aPrincipal,
-                                        aStoragePrincipal);
+  return StoragePrincipalHelper::Create(
+      aChannel, *aPrincipal, /* aForceIsolation */ true, aPartitionedPrincipal);
 }
 
 nsresult nsScriptSecurityManager::GetChannelResultPrincipal(
diff --git a/docshell/base/nsDocShell.cpp b/docshell/base/nsDocShell.cpp
index 86e2a43d54f0..700fe70ad521 100644
--- a/docshell/base/nsDocShell.cpp
+++ b/docshell/base/nsDocShell.cpp
@@ -6254,7 +6254,7 @@ nsresult nsDocShell::EnsureContentViewer() {
   nsCOMPtr<nsIContentSecurityPolicy> cspToInheritForAboutBlank;
   nsCOMPtr<nsIURI> baseURI;
   nsIPrincipal* principal = GetInheritedPrincipal(false);
-  nsIPrincipal* storagePrincipal = GetInheritedPrincipal(false, true);
+  nsIPrincipal* partitionedPrincipal = GetInheritedPrincipal(false, true);
 
   nsCOMPtr<nsIDocShellTreeItem> parentItem;
   GetInProcessSameTypeParent(getter_AddRefs(parentItem));
@@ -6269,7 +6269,7 @@ nsresult nsDocShell::EnsureContentViewer() {
   }
 
   nsresult rv = CreateAboutBlankContentViewer(
-      principal, storagePrincipal, cspToInheritForAboutBlank, baseURI);
+      principal, partitionedPrincipal, cspToInheritForAboutBlank, baseURI);
 
   NS_ENSURE_STATE(mContentViewer);
 
@@ -6295,7 +6295,7 @@ nsresult nsDocShell::EnsureContentViewer() {
 }
 
 nsresult nsDocShell::CreateAboutBlankContentViewer(
-    nsIPrincipal* aPrincipal, nsIPrincipal* aStoragePrincipal,
+    nsIPrincipal* aPrincipal, nsIPrincipal* aPartitionedPrincipal,
     nsIContentSecurityPolicy* aCSP, nsIURI* aBaseURI,
     bool aTryToSaveOldPresentation, bool aCheckPermitUnload,
     WindowGlobalChild* aActor) {
@@ -6389,7 +6389,7 @@ nsresult nsDocShell::CreateAboutBlankContentViewer(
           NS_LITERAL_CSTRING("text/html"));
 
   if (docFactory) {
-    nsCOMPtr<nsIPrincipal> principal, storagePrincipal;
+    nsCOMPtr<nsIPrincipal> principal, partitionedPrincipal;
     uint32_t sandboxFlags = mBrowsingContext->GetSandboxFlags();
     // If we're sandboxed, then create a new null principal. We skip
     // this if we're being created from WindowGlobalChild, since in
@@ -6403,17 +6403,17 @@ nsresult nsDocShell::CreateAboutBlankContentViewer(
       } else {
         principal = NullPrincipal::CreateWithInheritedAttributes(this);
       }
-      storagePrincipal = principal;
+      partitionedPrincipal = principal;
     } else {
       principal = aPrincipal;
-      storagePrincipal = aStoragePrincipal;
+      partitionedPrincipal = aPartitionedPrincipal;
     }
 
     MaybeCreateInitialClientSource(principal);
 
     // generate (about:blank) document to load
     blankDoc = nsContentDLF::CreateBlankDocument(mLoadGroup, principal,
-                                                 storagePrincipal, this);
+                                                 partitionedPrincipal, this);
     if (blankDoc) {
       // Hack: manually set the CSP for the new document
       // Please create an actual copy of the CSP (do not share the same
@@ -6465,9 +6465,9 @@ nsresult nsDocShell::CreateAboutBlankContentViewer(
 
 NS_IMETHODIMP
 nsDocShell::CreateAboutBlankContentViewer(nsIPrincipal* aPrincipal,
-                                          nsIPrincipal* aStoragePrincipal,
+                                          nsIPrincipal* aPartitionedPrincipal,
                                           nsIContentSecurityPolicy* aCSP) {
-  return CreateAboutBlankContentViewer(aPrincipal, aStoragePrincipal, aCSP,
+  return CreateAboutBlankContentViewer(aPrincipal, aPartitionedPrincipal, aCSP,
                                        nullptr);
 }
 
@@ -6475,7 +6475,7 @@ nsresult nsDocShell::CreateContentViewerForActor(
     WindowGlobalChild* aWindowActor) {
   MOZ_ASSERT(aWindowActor);
 
-  // FIXME: WindowGlobalChild should provide the StoragePrincipal.
+  // FIXME: WindowGlobalChild should provide the PartitionedPrincipal.
   nsresult rv = CreateAboutBlankContentViewer(
       aWindowActor->DocumentPrincipal(), aWindowActor->DocumentPrincipal(),
       /* aCsp */ nullptr,
@@ -8365,17 +8365,18 @@ nsresult nsDocShell::HandleSameDocumentNavigation(
    * recorded in session and global history.
    */
   nsCOMPtr<nsIPrincipal> newURITriggeringPrincipal, newURIPrincipalToInherit,
-      newURIStoragePrincipalToInherit;
+      newURIPartitionedPrincipalToInherit;
   nsCOMPtr<nsIContentSecurityPolicy> newCsp;
   if (mOSHE) {
     newURITriggeringPrincipal = mOSHE->GetTriggeringPrincipal();
     newURIPrincipalToInherit = mOSHE->GetPrincipalToInherit();
-    newURIStoragePrincipalToInherit = mOSHE->GetStoragePrincipalToInherit();
+    newURIPartitionedPrincipalToInherit =
+        mOSHE->GetPartitionedPrincipalToInherit();
     newCsp = mOSHE->GetCsp();
   } else {
     newURITriggeringPrincipal = aLoadState->TriggeringPrincipal();
     newURIPrincipalToInherit = doc->NodePrincipal();
-    newURIStoragePrincipalToInherit = doc->IntrinsicStoragePrincipal();
+    newURIPartitionedPrincipalToInherit = doc->PartitionedPrincipal();
     newCsp = doc->GetCsp();
   }
   // Pass true for aCloneSHChildren, since we're not
@@ -8387,8 +8388,8 @@ nsresult nsDocShell::HandleSameDocumentNavigation(
   // Anyway, aCloneSHChildren param is simply reflecting
   // doSameDocumentNavigation in this scope.
   OnNewURI(aLoadState->URI(), nullptr, newURITriggeringPrincipal,
-           newURIPrincipalToInherit, newURIStoragePrincipalToInherit, mLoadType,
-           newCsp, true, true, true);
+           newURIPrincipalToInherit, newURIPartitionedPrincipalToInherit,
+           mLoadType, newCsp, true, true, true);
 
   nsCOMPtr<nsIInputStream> postData;
   uint32_t cacheKey = 0;
@@ -8967,7 +8968,7 @@ bool nsDocShell::CanLoadInParentProcess(nsIURI* aURI) {
 }
 
 nsIPrincipal* nsDocShell::GetInheritedPrincipal(
-    bool aConsiderCurrentDocument, bool aConsiderStoragePrincipal) {
+    bool aConsiderCurrentDocument, bool aConsiderPartitionedPrincipal) {
   RefPtr<Document> document;
   bool inheritedFromCurrent = false;
 
@@ -9000,8 +9001,8 @@ nsIPrincipal* nsDocShell::GetInheritedPrincipal(
 
   //-- Get the document's principal
   if (document) {
-    nsIPrincipal* docPrincipal = aConsiderStoragePrincipal
-                                     ? document->IntrinsicStoragePrincipal()
+    nsIPrincipal* docPrincipal = aConsiderPartitionedPrincipal
+                                     ? document->PartitionedPrincipal()
                                      : document->NodePrincipal();
 
     // Don't allow loads in typeContent docShells to inherit the system
@@ -10024,7 +10025,7 @@ void nsDocShell::SetupReferrerInfoFromChannel(nsIChannel* aChannel) {
 bool nsDocShell::OnNewURI(nsIURI* aURI, nsIChannel* aChannel,
                           nsIPrincipal* aTriggeringPrincipal,
                           nsIPrincipal* aPrincipalToInherit,
-                          nsIPrincipal* aStoragePrincipalToInherit,
+                          nsIPrincipal* aPartitionedPrincipalToInherit,
                           uint32_t aLoadType, nsIContentSecurityPolicy* aCsp,
                           bool aFireOnLocationChange, bool aAddToGlobalHistory,
                           bool aCloneSHChildren) {
@@ -10189,8 +10190,9 @@ bool nsDocShell::OnNewURI(nsIURI* aURI, nsIChannel* aChannel,
        * rootDocShell
        */
       (void)AddToSessionHistory(aURI, aChannel, aTriggeringPrincipal,
-                                aPrincipalToInherit, aStoragePrincipalToInherit,
-                                aCsp, aCloneSHChildren, getter_AddRefs(mLSHE));
+                                aPrincipalToInherit,
+                                aPartitionedPrincipalToInherit, aCsp,
+                                aCloneSHChildren, getter_AddRefs(mLSHE));
     }
   } else if (GetSessionHistory() && mLSHE && mURIResultedInDocument) {
     // Even if we don't add anything to SHistory, ensure the current index
@@ -10659,7 +10661,8 @@ bool nsDocShell::ShouldAddToSessionHistory(nsIURI* aURI, nsIChannel* aChannel) {
 
 nsresult nsDocShell::AddToSessionHistory(
     nsIURI* aURI, nsIChannel* aChannel, nsIPrincipal* aTriggeringPrincipal,
-    nsIPrincipal* aPrincipalToInherit, nsIPrincipal* aStoragePrincipalToInherit,
+    nsIPrincipal* aPrincipalToInherit,
+    nsIPrincipal* aPartitionedPrincipalToInherit,
     nsIContentSecurityPolicy* aCsp, bool aCloneChildren,
     nsISHEntry** aNewEntry) {
   MOZ_ASSERT(aURI, "uri is null");
@@ -10718,7 +10721,8 @@ nsresult nsDocShell::AddToSessionHistory(
   uint32_t cacheKey = 0;
   nsCOMPtr<nsIPrincipal> triggeringPrincipal = aTriggeringPrincipal;
   nsCOMPtr<nsIPrincipal> principalToInherit = aPrincipalToInherit;
-  nsCOMPtr<nsIPrincipal> storagePrincipalToInherit = aStoragePrincipalToInherit;
+  nsCOMPtr<nsIPrincipal> partitionedPrincipalToInherit =
+      aPartitionedPrincipalToInherit;
   nsCOMPtr<nsIContentSecurityPolicy> csp = aCsp;
   bool expired = false;  // by default the page is not expired
   bool discardLayoutState = false;
@@ -10780,12 +10784,12 @@ nsresult nsDocShell::AddToSessionHistory(
       }
     }
 
-    if (!storagePrincipalToInherit) {
+    if (!partitionedPrincipalToInherit) {
       // XXXehsan is it correct to fall back to the principal to inherit in all
       // cases?  For example, what about the cases where we are using the load
       // info's principal to inherit?  Do we need to add a similar concept to
-      // load info for storage principal?
-      storagePrincipalToInherit = principalToInherit;
+      // load info for partitioned principal?
+      partitionedPrincipalToInherit = principalToInherit;
     }
   }
 
@@ -10828,10 +10832,10 @@ nsresult nsDocShell::AddToSessionHistory(
                 cacheKey,             // CacheKey
                 mContentTypeHint,     // Content-type
                 triggeringPrincipal,  // Channel or provided principal
-                principalToInherit, storagePrincipalToInherit, csp, HistoryID(),
-                mDynamicallyCreated, originalURI, resultPrincipalURI,
-                loadReplace, referrerInfo, srcdoc, srcdocEntry, baseURI,
-                saveLayoutState, expired);
+                principalToInherit, partitionedPrincipalToInherit, csp,
+                HistoryID(), mDynamicallyCreated, originalURI,
+                resultPrincipalURI, loadReplace, referrerInfo, srcdoc,
+                srcdocEntry, baseURI, saveLayoutState, expired);
 
   if (root == static_cast<nsIDocShellTreeItem*>(this) && GetSessionHistory()) {
     bool shouldPersist = ShouldAddToSessionHistory(aURI, aChannel);
@@ -10894,9 +10898,10 @@ nsresult nsDocShell::LoadHistoryEntry(nsISHEntry* aEntry, uint32_t aLoadType) {
     // Don't cache the presentation if we're going to just reload the
     // current entry. Caching would lead to trying to save the different
     // content viewers in the same nsISHEntry object.
-    rv = CreateAboutBlankContentViewer(loadState->PrincipalToInherit(),
-                                       loadState->StoragePrincipalToInherit(),
-                                       nullptr, nullptr, aEntry != mOSHE);
+    rv = CreateAboutBlankContentViewer(
+        loadState->PrincipalToInherit(),
+        loadState->PartitionedPrincipalToInherit(), nullptr, nullptr,
+        aEntry != mOSHE);
 
     if (NS_FAILED(rv)) {
       // The creation of the intermittent about:blank content
@@ -12101,7 +12106,7 @@ nsDocShell::InitOrReusePrintPreviewViewer(nsIWebBrowserPrint** aPrintPreview) {
         NullPrincipal::CreateWithInheritedAttributes(this);
     nsCOMPtr<nsIURI> uri;
     NS_NewURI(getter_AddRefs(uri), NS_LITERAL_CSTRING("about:printpreview"));
-    // Reuse the null principal for the storage principal.
+    // Reuse the null principal for the partitioned principal.
     // XXXehsan is that the right principal to use here?
     nsresult rv = CreateAboutBlankContentViewer(principal, principal,
                                                 /* aCsp = */ nullptr, uri);
diff --git a/docshell/base/nsDocShell.h b/docshell/base/nsDocShell.h
index dcffed8e5537..c2740aebe779 100644
--- a/docshell/base/nsDocShell.h
+++ b/docshell/base/nsDocShell.h
@@ -602,7 +602,7 @@ class nsDocShell final : public nsDocLoader,
   // passed in, the about:blank principal will end up being used.
   // aCSP, if any, will be used for the new about:blank load.
   nsresult CreateAboutBlankContentViewer(
-      nsIPrincipal* aPrincipal, nsIPrincipal* aStoragePrincipal,
+      nsIPrincipal* aPrincipal, nsIPrincipal* aPartitionedPrincipal,
       nsIContentSecurityPolicy* aCSP, nsIURI* aBaseURI,
       bool aTryToSaveOldPresentation = true, bool aCheckPermitUnload = true,
       mozilla::dom::WindowGlobalChild* aActor = nullptr);
@@ -642,7 +642,7 @@ class nsDocShell final : public nsDocLoader,
   nsresult AddToSessionHistory(nsIURI* aURI, nsIChannel* aChannel,
                                nsIPrincipal* aTriggeringPrincipal,
                                nsIPrincipal* aPrincipalToInherit,
-                               nsIPrincipal* aStoragePrincipalToInherit,
+                               nsIPrincipal* aPartitionedPrincipalToInherit,
                                nsIContentSecurityPolicy* aCsp,
                                bool aCloneChildren, nsISHEntry** aNewEntry);
 
@@ -717,9 +717,10 @@ class nsDocShell final : public nsDocLoader,
   bool OnNewURI(nsIURI* aURI, nsIChannel* aChannel,
                 nsIPrincipal* aTriggeringPrincipal,
                 nsIPrincipal* aPrincipalToInherit,
-                nsIPrincipal* aStoragePrincipalToInehrit, uint32_t aLoadType,
-                nsIContentSecurityPolicy* aCsp, bool aFireOnLocationChange,
-                bool aAddToGlobalHistory, bool aCloneSHChildren);
+                nsIPrincipal* aPartitionedPrincipalToInehrit,
+                uint32_t aLoadType, nsIContentSecurityPolicy* aCsp,
+                bool aFireOnLocationChange, bool aAddToGlobalHistory,
+                bool aCloneSHChildren);
 
   // Helper method that is called when a new document (including any
   // sub-documents - ie. frames) has been completely loaded.
@@ -757,10 +758,11 @@ class nsDocShell final : public nsDocLoader,
   // If that fails too, we force creation of a content viewer and use the
   // resulting principal. If aConsiderCurrentDocument is false, we just look
   // at the parent.
-  // If aConsiderStoragePrincipal is true, we consider the storage principal
-  // instead of the node principal.
-  nsIPrincipal* GetInheritedPrincipal(bool aConsiderCurrentDocument,
-                                      bool aConsiderStoragePrincipal = false);
+  // If aConsiderPartitionedPrincipal is true, we consider the partitioned
+  // principal instead of the node principal.
+  nsIPrincipal* GetInheritedPrincipal(
+      bool aConsiderCurrentDocument,
+      bool aConsiderPartitionedPrincipal = false);
 
   /**
    * Helper function that caches a URI and a transition for saving later.
diff --git a/docshell/base/nsDocShellLoadState.cpp b/docshell/base/nsDocShellLoadState.cpp
index 9f9b8f406fd4..d8a0bb461f18 100644
--- a/docshell/base/nsDocShellLoadState.cpp
+++ b/docshell/base/nsDocShellLoadState.cpp
@@ -127,7 +127,7 @@ nsDocShellLoadState::nsDocShellLoadState(
   mBaseURI = aLoadState.BaseURI();
   mTriggeringPrincipal = aLoadState.TriggeringPrincipal();
   mPrincipalToInherit = aLoadState.PrincipalToInherit();
-  mStoragePrincipalToInherit = aLoadState.StoragePrincipalToInherit();
+  mPartitionedPrincipalToInherit = aLoadState.PartitionedPrincipalToInherit();
   mCsp = aLoadState.Csp();
   mOriginalURIString = aLoadState.OriginalURIString();
   mCancelContentJSEpoch = aLoadState.CancelContentJSEpoch();
@@ -150,7 +150,7 @@ nsDocShellLoadState::nsDocShellLoadState(const nsDocShellLoadState& aOther)
       mInheritPrincipal(aOther.mInheritPrincipal),
       mPrincipalIsExplicit(aOther.mPrincipalIsExplicit),
       mPrincipalToInherit(aOther.mPrincipalToInherit),
-      mStoragePrincipalToInherit(aOther.mStoragePrincipalToInherit),
+      mPartitionedPrincipalToInherit(aOther.mPartitionedPrincipalToInherit),
       mForceAllowDataURI(aOther.mForceAllowDataURI),
       mOriginalFrameSrc(aOther.mOriginalFrameSrc),
       mIsFormSubmission(aOther.mIsFormSubmission),
@@ -432,13 +432,13 @@ void nsDocShellLoadState::SetPrincipalToInherit(
   mPrincipalToInherit = aPrincipalToInherit;
 }
 
-nsIPrincipal* nsDocShellLoadState::StoragePrincipalToInherit() const {
-  return mStoragePrincipalToInherit;
+nsIPrincipal* nsDocShellLoadState::PartitionedPrincipalToInherit() const {
+  return mPartitionedPrincipalToInherit;
 }
 
-void nsDocShellLoadState::SetStoragePrincipalToInherit(
-    nsIPrincipal* aStoragePrincipalToInherit) {
-  mStoragePrincipalToInherit = aStoragePrincipalToInherit;
+void nsDocShellLoadState::SetPartitionedPrincipalToInherit(
+    nsIPrincipal* aPartitionedPrincipalToInherit) {
+  mPartitionedPrincipalToInherit = aPartitionedPrincipalToInherit;
 }
 
 void nsDocShellLoadState::SetCsp(nsIContentSecurityPolicy* aCsp) {
@@ -885,7 +885,7 @@ DocShellLoadStateInit nsDocShellLoadState::Serialize() {
   loadState.BaseURI() = mBaseURI;
   loadState.TriggeringPrincipal() = mTriggeringPrincipal;
   loadState.PrincipalToInherit() = mPrincipalToInherit;
-  loadState.StoragePrincipalToInherit() = mStoragePrincipalToInherit;
+  loadState.PartitionedPrincipalToInherit() = mPartitionedPrincipalToInherit;
   loadState.Csp() = mCsp;
   loadState.OriginalURIString() = mOriginalURIString;
   loadState.CancelContentJSEpoch() = mCancelContentJSEpoch;
diff --git a/docshell/base/nsDocShellLoadState.h b/docshell/base/nsDocShellLoadState.h
index 91f0ab02edf5..68a5c3b06184 100644
--- a/docshell/base/nsDocShellLoadState.h
+++ b/docshell/base/nsDocShellLoadState.h
@@ -85,9 +85,10 @@ class nsDocShellLoadState final {
 
   void SetPrincipalToInherit(nsIPrincipal* aPrincipalToInherit);
 
-  nsIPrincipal* StoragePrincipalToInherit() const;
+  nsIPrincipal* PartitionedPrincipalToInherit() const;
 
-  void SetStoragePrincipalToInherit(nsIPrincipal* aStoragePrincipalToInherit);
+  void SetPartitionedPrincipalToInherit(
+      nsIPrincipal* aPartitionedPrincipalToInherit);
 
   bool LoadReplace() const;
 
@@ -332,7 +333,7 @@ class nsDocShellLoadState final {
 
   nsCOMPtr<nsIPrincipal> mPrincipalToInherit;
 
-  nsCOMPtr<nsIPrincipal> mStoragePrincipalToInherit;
+  nsCOMPtr<nsIPrincipal> mPartitionedPrincipalToInherit;
 
   // If this attribute is true, then a top-level navigation
   // to a data URI will be allowed.
diff --git a/docshell/base/nsIDocShell.idl b/docshell/base/nsIDocShell.idl
index 01dc4734eb19..c9af7d7692c9 100644
--- a/docshell/base/nsIDocShell.idl
+++ b/docshell/base/nsIDocShell.idl
@@ -545,11 +545,12 @@ interface nsIDocShell : nsIDocShellTreeItem
   /**
    * Create a new about:blank document and content viewer.
    * @param aPrincipal the principal to use for the new document.
-   * @param aStoragePrincipal the storage principal to use for the new document.
+   * @param aPartitionedPrincipal the partitioned principal to use for the new
+   *        document.
    * @param aCsp the CSP to use for the new document.
    */
   void createAboutBlankContentViewer(in nsIPrincipal aPrincipal,
-                                     in nsIPrincipal aStoragePrincipal,
+                                     in nsIPrincipal aPartitionedPrincipal,
                                      [optional] in nsIContentSecurityPolicy aCSP);
 
   /**
diff --git a/docshell/shistory/SessionHistoryEntry.cpp b/docshell/shistory/SessionHistoryEntry.cpp
index 07a28d1291c9..fc82f0c9a596 100644
--- a/docshell/shistory/SessionHistoryEntry.cpp
+++ b/docshell/shistory/SessionHistoryEntry.cpp
@@ -47,8 +47,8 @@ SessionHistoryEntry::SessionHistoryEntry(nsISHistory* aSessionHistory,
       mID(++gEntryID) {
   mSharedInfo->mTriggeringPrincipal = aLoadState->TriggeringPrincipal();
   mSharedInfo->mPrincipalToInherit = aLoadState->PrincipalToInherit();
-  mSharedInfo->mStoragePrincipalToInherit =
-      aLoadState->StoragePrincipalToInherit();
+  mSharedInfo->mPartitionedPrincipalToInherit =
+      aLoadState->PartitionedPrincipalToInherit();
   mSharedInfo->mCsp = aLoadState->Csp();
   // FIXME Set remaining shared fields!
 }
@@ -348,18 +348,18 @@ SessionHistoryEntry::SetPrincipalToInherit(nsIPrincipal* aPrincipalToInherit) {
 }
 
 NS_IMETHODIMP
-SessionHistoryEntry::GetStoragePrincipalToInherit(
-    nsIPrincipal** aStoragePrincipalToInherit) {
-  nsCOMPtr<nsIPrincipal> storagePrincipalToInherit =
-      mSharedInfo->mStoragePrincipalToInherit;
-  storagePrincipalToInherit.forget(aStoragePrincipalToInherit);
+SessionHistoryEntry::GetPartitionedPrincipalToInherit(
+    nsIPrincipal** aPartitionedPrincipalToInherit) {
+  nsCOMPtr<nsIPrincipal> partitionedPrincipalToInherit =
+      mSharedInfo->mPartitionedPrincipalToInherit;
+  partitionedPrincipalToInherit.forget(aPartitionedPrincipalToInherit);
   return NS_OK;
 }
 
 NS_IMETHODIMP
-SessionHistoryEntry::SetStoragePrincipalToInherit(
-    nsIPrincipal* aStoragePrincipalToInherit) {
-  mSharedInfo->mStoragePrincipalToInherit = aStoragePrincipalToInherit;
+SessionHistoryEntry::SetPartitionedPrincipalToInherit(
+    nsIPrincipal* aPartitionedPrincipalToInherit) {
+  mSharedInfo->mPartitionedPrincipalToInherit = aPartitionedPrincipalToInherit;
   return NS_OK;
 }
 
@@ -553,11 +553,11 @@ SessionHistoryEntry::Create(
     nsIURI* aURI, const nsAString& aTitle, nsIInputStream* aInputStream,
     uint32_t aCacheKey, const nsACString& aContentType,
     nsIPrincipal* aTriggeringPrincipal, nsIPrincipal* aPrincipalToInherit,
-    nsIPrincipal* aStoragePrincipalToInherit, nsIContentSecurityPolicy* aCsp,
-    const nsID& aDocshellID, bool aDynamicCreation, nsIURI* aOriginalURI,
-    nsIURI* aResultPrincipalURI, bool aLoadReplace,
-    nsIReferrerInfo* aReferrerInfo, const nsAString& aSrcdoc, bool aSrcdocEntry,
-    nsIURI* aBaseURI, bool aSaveLayoutState, bool aExpired) {
+    nsIPrincipal* aPartitionedPrincipalToInherit,
+    nsIContentSecurityPolicy* aCsp, const nsID& aDocshellID,
+    bool aDynamicCreation, nsIURI* aOriginalURI, nsIURI* aResultPrincipalURI,
+    bool aLoadReplace, nsIReferrerInfo* aReferrerInfo, const nsAString& aSrcdoc,
+    bool aSrcdocEntry, nsIURI* aBaseURI, bool aSaveLayoutState, bool aExpired) {
   MOZ_CRASH("Might need to implement this");
   return NS_ERROR_NOT_IMPLEMENTED;
 }
@@ -690,8 +690,8 @@ SessionHistoryEntry::CreateLoadInfo(nsDocShellLoadState** aLoadState) {
   loadState->SetTypeHint(mSharedInfo->mContentType);
   loadState->SetTriggeringPrincipal(mSharedInfo->mTriggeringPrincipal);
   loadState->SetPrincipalToInherit(mSharedInfo->mPrincipalToInherit);
-  loadState->SetStoragePrincipalToInherit(
-      mSharedInfo->mStoragePrincipalToInherit);
+  loadState->SetPartitionedPrincipalToInherit(
+      mSharedInfo->mPartitionedPrincipalToInherit);
   loadState->SetCsp(mSharedInfo->mCsp);
 
   // Do not inherit principal from document (security-critical!);
diff --git a/docshell/shistory/nsISHEntry.idl b/docshell/shistory/nsISHEntry.idl
index 8bbf2a68687c..cae34bc82125 100644
--- a/docshell/shistory/nsISHEntry.idl
+++ b/docshell/shistory/nsISHEntry.idl
@@ -164,7 +164,7 @@ interface nsISHEntry : nsISupports
      * Get the storage principal, if any, that is used when the inherit flag is
      * set.
      */
-    [infallible] attribute nsIPrincipal storagePrincipalToInherit;
+    [infallible] attribute nsIPrincipal partitionedPrincipalToInherit;
 
     /**
      * Get the csp, if any, that was used for this document load. That
@@ -298,7 +298,7 @@ interface nsISHEntry : nsISupports
                            in ACString contentType,
                            in nsIPrincipal triggeringPrincipal,
                            in nsIPrincipal principalToInherit,
-                           in nsIPrincipal storagePrincipalToInherit,
+                           in nsIPrincipal partitionedPrincipalToInherit,
                            in nsIContentSecurityPolicy aCsp,
                            in nsIDRef docshellID,
                            in boolean dynamicCreation,
diff --git a/docshell/shistory/nsSHEntry.cpp b/docshell/shistory/nsSHEntry.cpp
index 229b15eff25d..1ffb9406d123 100644
--- a/docshell/shistory/nsSHEntry.cpp
+++ b/docshell/shistory/nsSHEntry.cpp
@@ -323,15 +323,18 @@ nsSHEntry::SetContentType(const nsACString& aContentType) {
 }
 
 NS_IMETHODIMP
-nsSHEntry::Create(
-    nsIURI* aURI, const nsAString& aTitle, nsIInputStream* aInputStream,
-    uint32_t aCacheKey, const nsACString& aContentType,
-    nsIPrincipal* aTriggeringPrincipal, nsIPrincipal* aPrincipalToInherit,
-    nsIPrincipal* aStoragePrincipalToInherit, nsIContentSecurityPolicy* aCsp,
-    const nsID& aDocShellID, bool aDynamicCreation, nsIURI* aOriginalURI,
-    nsIURI* aResultPrincipalURI, bool aLoadReplace,
-    nsIReferrerInfo* aReferrerInfo, const nsAString& aSrcdocData,
-    bool aSrcdocEntry, nsIURI* aBaseURI, bool aSaveLayoutState, bool aExpired) {
+nsSHEntry::Create(nsIURI* aURI, const nsAString& aTitle,
+                  nsIInputStream* aInputStream, uint32_t aCacheKey,
+                  const nsACString& aContentType,
+                  nsIPrincipal* aTriggeringPrincipal,
+                  nsIPrincipal* aPrincipalToInherit,
+                  nsIPrincipal* aPartitionedPrincipalToInherit,
+                  nsIContentSecurityPolicy* aCsp, const nsID& aDocShellID,
+                  bool aDynamicCreation, nsIURI* aOriginalURI,
+                  nsIURI* aResultPrincipalURI, bool aLoadReplace,
+                  nsIReferrerInfo* aReferrerInfo, const nsAString& aSrcdocData,
+                  bool aSrcdocEntry, nsIURI* aBaseURI, bool aSaveLayoutState,
+                  bool aExpired) {
   MOZ_ASSERT(
       aTriggeringPrincipal,
       "need a valid triggeringPrincipal to create a session history entry");
@@ -347,7 +350,7 @@ nsSHEntry::Create(
   mShared->mContentType = aContentType;
   mShared->mTriggeringPrincipal = aTriggeringPrincipal;
   mShared->mPrincipalToInherit = aPrincipalToInherit;
-  mShared->mStoragePrincipalToInherit = aStoragePrincipalToInherit;
+  mShared->mPartitionedPrincipalToInherit = aPartitionedPrincipalToInherit;
   mShared->mCsp = aCsp;
   mShared->mDocShellID = aDocShellID;
   mShared->mDynamicallyCreated = aDynamicCreation;
@@ -431,17 +434,17 @@ nsSHEntry::SetPrincipalToInherit(nsIPrincipal* aPrincipalToInherit) {
 }
 
 NS_IMETHODIMP
-nsSHEntry::GetStoragePrincipalToInherit(
-    nsIPrincipal** aStoragePrincipalToInherit) {
-  NS_IF_ADDREF(*aStoragePrincipalToInherit =
-                   mShared->mStoragePrincipalToInherit);
+nsSHEntry::GetPartitionedPrincipalToInherit(
+    nsIPrincipal** aPartitionedPrincipalToInherit) {
+  NS_IF_ADDREF(*aPartitionedPrincipalToInherit =
+                   mShared->mPartitionedPrincipalToInherit);
   return NS_OK;
 }
 
 NS_IMETHODIMP
-nsSHEntry::SetStoragePrincipalToInherit(
-    nsIPrincipal* aStoragePrincipalToInherit) {
-  mShared->mStoragePrincipalToInherit = aStoragePrincipalToInherit;
+nsSHEntry::SetPartitionedPrincipalToInherit(
+    nsIPrincipal* aPartitionedPrincipalToInherit) {
+  mShared->mPartitionedPrincipalToInherit = aPartitionedPrincipalToInherit;
   return NS_OK;
 }
 
@@ -849,9 +852,9 @@ nsSHEntry::CreateLoadInfo(nsDocShellLoadState** aLoadState) {
   loadState->SetTriggeringPrincipal(triggeringPrincipal);
   nsCOMPtr<nsIPrincipal> principalToInherit = GetPrincipalToInherit();
   loadState->SetPrincipalToInherit(principalToInherit);
-  nsCOMPtr<nsIPrincipal> storagePrincipalToInherit =
-      GetStoragePrincipalToInherit();
-  loadState->SetStoragePrincipalToInherit(storagePrincipalToInherit);
+  nsCOMPtr<nsIPrincipal> partitionedPrincipalToInherit =
+      GetPartitionedPrincipalToInherit();
+  loadState->SetPartitionedPrincipalToInherit(partitionedPrincipalToInherit);
   nsCOMPtr<nsIContentSecurityPolicy> csp = GetCsp();
   loadState->SetCsp(csp);
   nsCOMPtr<nsIReferrerInfo> referrerInfo = GetReferrerInfo();
diff --git a/docshell/shistory/nsSHEntryShared.cpp b/docshell/shistory/nsSHEntryShared.cpp
index ba8df89a135d..e16488e6712b 100644
--- a/docshell/shistory/nsSHEntryShared.cpp
+++ b/docshell/shistory/nsSHEntryShared.cpp
@@ -51,7 +51,7 @@ void SHEntrySharedParentState::CopyFrom(SHEntrySharedParentState* aEntry) {
   mDocShellID = aEntry->mDocShellID;
   mTriggeringPrincipal = aEntry->mTriggeringPrincipal;
   mPrincipalToInherit = aEntry->mPrincipalToInherit;
-  mStoragePrincipalToInherit = aEntry->mStoragePrincipalToInherit;
+  mPartitionedPrincipalToInherit = aEntry->mPartitionedPrincipalToInherit;
   mCsp = aEntry->mCsp;
   mSaveLayoutState = aEntry->mSaveLayoutState;
   mContentType.Assign(aEntry->mContentType);
diff --git a/docshell/shistory/nsSHEntryShared.h b/docshell/shistory/nsSHEntryShared.h
index 3d128eec5a95..4212d2816e9d 100644
--- a/docshell/shistory/nsSHEntryShared.h
+++ b/docshell/shistory/nsSHEntryShared.h
@@ -72,7 +72,7 @@ class SHEntrySharedParentState {
   nsID mDocShellID;
   nsCOMPtr<nsIPrincipal> mTriggeringPrincipal;
   nsCOMPtr<nsIPrincipal> mPrincipalToInherit;
-  nsCOMPtr<nsIPrincipal> mStoragePrincipalToInherit;
+  nsCOMPtr<nsIPrincipal> mPartitionedPrincipalToInherit;
   nsCOMPtr<nsIContentSecurityPolicy> mCsp;
   // Child side updates layout history state when page is being unloaded or
   // moved to bfcache.
diff --git a/dom/base/Document.cpp b/dom/base/Document.cpp
index bc9db0bc26b2..96a04bfe9e61 100644
--- a/dom/base/Document.cpp
+++ b/dom/base/Document.cpp
@@ -2412,7 +2412,7 @@ bool Document::IsVisibleConsideringAncestors() const {
 void Document::Reset(nsIChannel* aChannel, nsILoadGroup* aLoadGroup) {
   nsCOMPtr<nsIURI> uri;
   nsCOMPtr<nsIPrincipal> principal;
-  nsCOMPtr<nsIPrincipal> storagePrincipal;
+  nsCOMPtr<nsIPrincipal> partitionedPrincipal;
   if (aChannel) {
     // Note: this code is duplicated in PrototypeDocumentContentSink::Init and
     // nsScriptSecurityManager::GetChannelResultPrincipals.
@@ -2425,20 +2425,20 @@ void Document::Reset(nsIChannel* aChannel, nsILoadGroup* aLoadGroup) {
     if (securityManager) {
       securityManager->GetChannelResultPrincipals(
           aChannel, getter_AddRefs(principal),
-          getter_AddRefs(storagePrincipal));
+          getter_AddRefs(partitionedPrincipal));
     }
   }
 
-  bool equal = principal->Equals(storagePrincipal);
+  bool equal = principal->Equals(partitionedPrincipal);
 
   principal = MaybeDowngradePrincipal(principal);
   if (equal) {
-    storagePrincipal = principal;
+    partitionedPrincipal = principal;
   } else {
-    storagePrincipal = MaybeDowngradePrincipal(storagePrincipal);
+    partitionedPrincipal = MaybeDowngradePrincipal(partitionedPrincipal);
   }
 
-  ResetToURI(uri, aLoadGroup, principal, storagePrincipal);
+  ResetToURI(uri, aLoadGroup, principal, partitionedPrincipal);
 
   // Note that, since mTiming does not change during a reset, the
   // navigationStart time remains unchanged and therefore any future new
@@ -2500,9 +2500,9 @@ void Document::DisconnectNodeTree() {
 
 void Document::ResetToURI(nsIURI* aURI, nsILoadGroup* aLoadGroup,
                           nsIPrincipal* aPrincipal,
-                          nsIPrincipal* aStoragePrincipal) {
+                          nsIPrincipal* aPartitionedPrincipal) {
   MOZ_ASSERT(aURI, "Null URI passed to ResetToURI");
-  MOZ_ASSERT(!!aPrincipal == !!aStoragePrincipal);
+  MOZ_ASSERT(!!aPrincipal == !!aPartitionedPrincipal);
 
   MOZ_LOG(gDocumentLeakPRLog, LogLevel::Debug,
           ("DOCUMENT %p ResetToURI %s", this, aURI->GetSpecOrDefault().get()));
@@ -2587,7 +2587,7 @@ void Document::ResetToURI(nsIURI* aURI, nsILoadGroup* aLoadGroup,
 
   // Now get our new principal
   if (aPrincipal) {
-    SetPrincipals(aPrincipal, aStoragePrincipal);
+    SetPrincipals(aPrincipal, aPartitionedPrincipal);
   } else {
     nsIScriptSecurityManager* securityManager =
         nsContentUtils::GetSecurityManager();
@@ -3717,8 +3717,8 @@ void Document::RemoveFromIdTable(Element* aElement, nsAtom* aId) {
 }
 
 void Document::SetPrincipals(nsIPrincipal* aNewPrincipal,
-                             nsIPrincipal* aNewStoragePrincipal) {
-  MOZ_ASSERT(!!aNewPrincipal == !!aNewStoragePrincipal);
+                             nsIPrincipal* aNewPartitionedPrincipal) {
+  MOZ_ASSERT(!!aNewPrincipal == !!aNewPartitionedPrincipal);
   if (aNewPrincipal && mAllowDNSPrefetch &&
       StaticPrefs::network_dns_disablePrefetchFromHTTPS()) {
     if (aNewPrincipal->SchemeIs("https")) {
@@ -3726,7 +3726,7 @@ void Document::SetPrincipals(nsIPrincipal* aNewPrincipal,
     }
   }
   mNodeInfoManager->SetDocumentPrincipal(aNewPrincipal);
-  mIntrinsicStoragePrincipal = aNewStoragePrincipal;
+  mPartitionedPrincipal = aNewPartitionedPrincipal;
 
   ContentBlockingAllowList::ComputePrincipal(
       aNewPrincipal, getter_AddRefs(mContentBlockingAllowListPrincipal));
@@ -11057,8 +11057,7 @@ nsresult Document::CloneDocHelper(Document* clone) const {
     }
     clone->mChannel = channel;
     if (uri) {
-      clone->ResetToURI(uri, loadGroup, NodePrincipal(),
-                        EffectiveStoragePrincipal());
+      clone->ResetToURI(uri, loadGroup, NodePrincipal(), mPartitionedPrincipal);
     }
 
     clone->SetContainer(mDocumentContainer);
@@ -11082,7 +11081,7 @@ nsresult Document::CloneDocHelper(Document* clone) const {
   // them.
   clone->SetDocumentURI(Document::GetDocumentURI());
   clone->SetChromeXHRDocURI(mChromeXHRDocURI);
-  clone->SetPrincipals(NodePrincipal(), mIntrinsicStoragePrincipal);
+  clone->SetPrincipals(NodePrincipal(), mPartitionedPrincipal);
   clone->mActiveStoragePrincipal = mActiveStoragePrincipal;
   clone->mDocumentBaseURI = mDocumentBaseURI;
   clone->SetChromeXHRDocBaseURI(mChromeXHRDocBaseURI);
@@ -16302,7 +16301,7 @@ nsIPrincipal* Document::EffectiveStoragePrincipal() const {
     return mActiveStoragePrincipal = NodePrincipal();
   }
 
-  return mActiveStoragePrincipal = mIntrinsicStoragePrincipal;
+  return mActiveStoragePrincipal = mPartitionedPrincipal;
 }
 
 void Document::SetIsInitialDocument(bool aIsInitialDocument) {
diff --git a/dom/base/Document.h b/dom/base/Document.h
index 0c0319f9b19c..fe53de787edf 100644
--- a/dom/base/Document.h
+++ b/dom/base/Document.h
@@ -578,13 +578,11 @@ class Document : public nsINode,
     return EffectiveStoragePrincipal();
   }
 
-  // You should probably not be using this function, since it performs no
-  // checks to ensure that the intrinsic storage principal should really be
-  // used here.  It is only designed to be used in very specific circumstances,
-  // such as when inheriting the document/storage principal.
-  nsIPrincipal* IntrinsicStoragePrincipal() final {
-    return mIntrinsicStoragePrincipal;
-  }
+  // You should probably not be using this function, since it performs no checks
+  // to ensure that the partitioned principal should really be used here.  It is
+  // only designed to be used in very specific circumstances, such as when
+  // inheriting the document/storage principal.
+  nsIPrincipal* PartitionedPrincipal() final { return mPartitionedPrincipal; }
 
   void ClearActiveStoragePrincipal() { mActiveStoragePrincipal = nullptr; }
 
@@ -855,7 +853,8 @@ class Document : public nsINode,
    * Set the principals responsible for this document.  Chances are, you do not
    * want to be using this.
    */
-  void SetPrincipals(nsIPrincipal* aPrincipal, nsIPrincipal* aStoragePrincipal);
+  void SetPrincipals(nsIPrincipal* aPrincipal,
+                     nsIPrincipal* aPartitionedPrincipal);
 
   /**
    * Get the list of ancestor principals for a document.  This is the same as
@@ -2089,13 +2088,13 @@ class Document : public nsINode,
   virtual void Reset(nsIChannel* aChannel, nsILoadGroup* aLoadGroup);
 
   /**
-   * Reset this document to aURI, aLoadGroup, aPrincipal and aStoragePrincipal.
-   * aURI must not be null.  If aPrincipal is null, a content principal based
-   * on aURI will be used.
+   * Reset this document to aURI, aLoadGroup, aPrincipal and
+   * aPartitionedPrincipal.  aURI must not be null.  If aPrincipal is null, a
+   * content principal based on aURI will be used.
    */
   virtual void ResetToURI(nsIURI* aURI, nsILoadGroup* aLoadGroup,
                           nsIPrincipal* aPrincipal,
-                          nsIPrincipal* aStoragePrincipal);
+                          nsIPrincipal* aPartitionedPrincipal);
 
   /**
    * Set the container (docshell) for this document. Virtual so that
@@ -5046,8 +5045,9 @@ class Document : public nsINode,
   int32_t mCachedTabSizeGeneration;
   nsTabSizes mCachedTabSizes;
 
-  // The principal to use for the storage area of this document.
-  nsCOMPtr<nsIPrincipal> mIntrinsicStoragePrincipal;
+  // This is equal to document's principal but with an isolation key. See
+  // StoragePrincipalHelper.h to know more.
+  nsCOMPtr<nsIPrincipal> mPartitionedPrincipal;
 
   // The cached storage principal for this document.
   // This is mutable so that we can keep EffectiveStoragePrincipal() const
diff --git a/dom/base/nsGlobalWindowInner.cpp b/dom/base/nsGlobalWindowInner.cpp
index ef5929e19787..cfd84c7ce55d 100644
--- a/dom/base/nsGlobalWindowInner.cpp
+++ b/dom/base/nsGlobalWindowInner.cpp
@@ -1099,7 +1099,7 @@ void nsGlobalWindowInner::FreeInnerObjects() {
     // Remember the document's principal, URI, and CSP.
     mDocumentPrincipal = mDoc->NodePrincipal();
     mDocumentStoragePrincipal = mDoc->EffectiveStoragePrincipal();
-    mDocumentIntrinsicStoragePrincipal = mDoc->IntrinsicStoragePrincipal();
+    mDocumentPartitionedPrincipal = mDoc->PartitionedPrincipal();
     mDocumentURI = mDoc->GetDocumentURI();
     mDocBaseURI = mDoc->GetDocBaseURI();
     mDocContentBlockingAllowListPrincipal =
@@ -1327,7 +1327,7 @@ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INTERNAL(nsGlobalWindowInner)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mIndexedDB)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDocumentPrincipal)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDocumentStoragePrincipal)
-  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDocumentIntrinsicStoragePrincipal)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDocumentPartitionedPrincipal)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDocumentCsp)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mBrowserChild)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDoc)
@@ -1434,7 +1434,7 @@ NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsGlobalWindowInner)
   }
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mDocumentPrincipal)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mDocumentStoragePrincipal)
-  NS_IMPL_CYCLE_COLLECTION_UNLINK(mDocumentIntrinsicStoragePrincipal)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mDocumentPartitionedPrincipal)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mDocumentCsp)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mBrowserChild)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mDoc)
@@ -2102,24 +2102,24 @@ nsIPrincipal* nsGlobalWindowInner::GetEffectiveStoragePrincipal() {
   return nullptr;
 }
 
-nsIPrincipal* nsGlobalWindowInner::IntrinsicStoragePrincipal() {
+nsIPrincipal* nsGlobalWindowInner::PartitionedPrincipal() {
   if (mDoc) {
     // If we have a document, get the principal from the document
-    return mDoc->EffectiveStoragePrincipal();
+    return mDoc->PartitionedPrincipal();
   }
 
-  if (mDocumentIntrinsicStoragePrincipal) {
-    return mDocumentIntrinsicStoragePrincipal;
+  if (mDocumentPartitionedPrincipal) {
+    return mDocumentPartitionedPrincipal;
   }
 
-  // If we don't have a storage principal and we don't have a document we ask
-  // the parent window for the storage principal.
+  // If we don't have a partitioned principal and we don't have a document we
+  // ask the parent window for the partitioned principal.
 
   nsCOMPtr<nsIScriptObjectPrincipal> objPrincipal =
       do_QueryInterface(GetInProcessParentInternal());
 
   if (objPrincipal) {
-    return objPrincipal->IntrinsicStoragePrincipal();
+    return objPrincipal->PartitionedPrincipal();
   }
 
   return nullptr;
@@ -4346,10 +4346,10 @@ already_AddRefed<nsICSSDeclaration> nsGlobalWindowInner::GetComputedStyleHelper(
 
 Storage* nsGlobalWindowInner::GetSessionStorage(ErrorResult& aError) {
   nsIPrincipal* principal = GetPrincipal();
-  nsIPrincipal* storagePrincipal = IntrinsicStoragePrincipal();
+  nsIPrincipal* partitionedPrincipal = PartitionedPrincipal();
   BrowsingContext* browsingContext = GetBrowsingContext();
 
-  if (!principal || !storagePrincipal || !browsingContext ||
+  if (!principal || !partitionedPrincipal || !browsingContext ||
       !Storage::StoragePrefIsEnabled()) {
     return nullptr;
   }
@@ -4360,7 +4360,7 @@ Storage* nsGlobalWindowInner::GetSessionStorage(ErrorResult& aError) {
              mSessionStorage.get()));
     bool canAccess =
         principal->Subsumes(mSessionStorage->Principal()) &&
-        storagePrincipal->Subsumes(mSessionStorage->StoragePrincipal());
+        partitionedPrincipal->Subsumes(mSessionStorage->StoragePrincipal());
     if (!canAccess) {
       mSessionStorage = nullptr;
     }
@@ -4438,9 +4438,9 @@ Storage* nsGlobalWindowInner::GetSessionStorage(ErrorResult& aError) {
     }
 
     RefPtr<Storage> storage;
-    aError = storageManager->CreateStorage(this, principal, storagePrincipal,
-                                           documentURI, IsPrivateBrowsing(),
-                                           getter_AddRefs(storage));
+    aError = storageManager->CreateStorage(
+        this, principal, partitionedPrincipal, documentURI, IsPrivateBrowsing(),
+        getter_AddRefs(storage));
     if (aError.Failed()) {
       return nullptr;
     }
@@ -5023,11 +5023,6 @@ void nsGlobalWindowInner::ObserveStorageNotification(
     return;
   }
 
-  nsIPrincipal* storagePrincipal = GetEffectiveStoragePrincipal();
-  if (!storagePrincipal) {
-    return;
-  }
-
   bool fireMozStorageChanged = false;
   nsAutoString eventType;
   eventType.AssignLiteral("storage");
@@ -5040,7 +5035,7 @@ void nsGlobalWindowInner::ObserveStorageNotification(
 
     if (const RefPtr<SessionStorageManager> storageManager =
             GetBrowsingContext()->GetSessionStorageManager()) {
-      nsresult rv = storageManager->CheckStorage(storagePrincipal,
+      nsresult rv = storageManager->CheckStorage(PartitionedPrincipal(),
                                                  changingStorage, &check);
       if (NS_FAILED(rv)) {
         return;
@@ -5067,6 +5062,11 @@ void nsGlobalWindowInner::ObserveStorageNotification(
   else {
     MOZ_ASSERT(!NS_strcmp(aStorageType, u"localStorage"));
 
+    nsIPrincipal* storagePrincipal = GetEffectiveStoragePrincipal();
+    if (!storagePrincipal) {
+      return;
+    }
+
     MOZ_DIAGNOSTIC_ASSERT(StorageUtils::PrincipalsEqual(aEvent->GetPrincipal(),
                                                         storagePrincipal));
 
diff --git a/dom/base/nsGlobalWindowInner.h b/dom/base/nsGlobalWindowInner.h
index fbed52ff197b..f4fd5af0f3d1 100644
--- a/dom/base/nsGlobalWindowInner.h
+++ b/dom/base/nsGlobalWindowInner.h
@@ -266,7 +266,7 @@ class nsGlobalWindowInner final : public mozilla::dom::EventTarget,
 
   virtual nsIPrincipal* GetEffectiveStoragePrincipal() override;
 
-  virtual nsIPrincipal* IntrinsicStoragePrincipal() override;
+  virtual nsIPrincipal* PartitionedPrincipal() override;
 
   // nsIDOMWindow
   NS_DECL_NSIDOMWINDOW
@@ -1339,7 +1339,7 @@ class nsGlobalWindowInner final : public mozilla::dom::EventTarget,
   // FreeInnerObjects has been called.
   nsCOMPtr<nsIPrincipal> mDocumentPrincipal;
   nsCOMPtr<nsIPrincipal> mDocumentStoragePrincipal;
-  nsCOMPtr<nsIPrincipal> mDocumentIntrinsicStoragePrincipal;
+  nsCOMPtr<nsIPrincipal> mDocumentPartitionedPrincipal;
   nsCOMPtr<nsIContentSecurityPolicy> mDocumentCsp;
 
   RefPtr<mozilla::dom::DebuggerNotificationManager>
diff --git a/dom/base/nsGlobalWindowOuter.cpp b/dom/base/nsGlobalWindowOuter.cpp
index de833141ad19..d65921890ece 100644
--- a/dom/base/nsGlobalWindowOuter.cpp
+++ b/dom/base/nsGlobalWindowOuter.cpp
@@ -1588,7 +1588,7 @@ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INTERNAL(nsGlobalWindowOuter)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mSuspendedDoc)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDocumentPrincipal)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDocumentStoragePrincipal)
-  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDocumentIntrinsicStoragePrincipal)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDocumentPartitionedPrincipal)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDoc)
 
   // Traverse stuff from nsPIDOMWindow
@@ -1620,7 +1620,7 @@ NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsGlobalWindowOuter)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mSuspendedDoc)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mDocumentPrincipal)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mDocumentStoragePrincipal)
-  NS_IMPL_CYCLE_COLLECTION_UNLINK(mDocumentIntrinsicStoragePrincipal)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mDocumentPartitionedPrincipal)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mDoc)
 
   // Unlink stuff from nsPIDOMWindow
@@ -2044,8 +2044,8 @@ nsresult nsGlobalWindowOuter::SetNewDocument(Document* aDocument,
              "mDocumentPrincipal prematurely set!");
   MOZ_ASSERT(mDocumentStoragePrincipal == nullptr,
              "mDocumentStoragePrincipal prematurely set!");
-  MOZ_ASSERT(mDocumentIntrinsicStoragePrincipal == nullptr,
-             "mDocumentIntrinsicStoragePrincipal prematurely set!");
+  MOZ_ASSERT(mDocumentPartitionedPrincipal == nullptr,
+             "mDocumentPartitionedPrincipal prematurely set!");
   MOZ_ASSERT(aDocument);
 
   // Bail out early if we're in process of closing down the window.
@@ -2697,7 +2697,7 @@ void nsGlobalWindowOuter::DetachFromDocShell(bool aIsBeingDiscarded) {
     // Remember the document's principal and URI.
     mDocumentPrincipal = mDoc->NodePrincipal();
     mDocumentStoragePrincipal = mDoc->EffectiveStoragePrincipal();
-    mDocumentIntrinsicStoragePrincipal = mDoc->IntrinsicStoragePrincipal();
+    mDocumentPartitionedPrincipal = mDoc->PartitionedPrincipal();
     mDocumentURI = mDoc->GetDocumentURI();
 
     // Release our document reference
@@ -2970,24 +2970,24 @@ nsIPrincipal* nsGlobalWindowOuter::GetEffectiveStoragePrincipal() {
   return nullptr;
 }
 
-nsIPrincipal* nsGlobalWindowOuter::IntrinsicStoragePrincipal() {
+nsIPrincipal* nsGlobalWindowOuter::PartitionedPrincipal() {
   if (mDoc) {
     // If we have a document, get the principal from the document
-    return mDoc->IntrinsicStoragePrincipal();
+    return mDoc->PartitionedPrincipal();
   }
 
-  if (mDocumentIntrinsicStoragePrincipal) {
-    return mDocumentIntrinsicStoragePrincipal;
+  if (mDocumentPartitionedPrincipal) {
+    return mDocumentPartitionedPrincipal;
   }
 
-  // If we don't have a storage principal and we don't have a document we ask
-  // the parent window for the storage principal.
+  // If we don't have a partitioned principal and we don't have a document we
+  // ask the parent window for the partitioned principal.
 
   nsCOMPtr<nsIScriptObjectPrincipal> objPrincipal =
       do_QueryInterface(GetInProcessParentInternal());
 
   if (objPrincipal) {
-    return objPrincipal->IntrinsicStoragePrincipal();
+    return objPrincipal->PartitionedPrincipal();
   }
 
   return nullptr;
diff --git a/dom/base/nsGlobalWindowOuter.h b/dom/base/nsGlobalWindowOuter.h
index 8f7f489ca9a3..a74656a56024 100644
--- a/dom/base/nsGlobalWindowOuter.h
+++ b/dom/base/nsGlobalWindowOuter.h
@@ -244,7 +244,7 @@ class nsGlobalWindowOuter final : public mozilla::dom::EventTarget,
 
   virtual nsIPrincipal* GetEffectiveStoragePrincipal() override;
 
-  virtual nsIPrincipal* IntrinsicStoragePrincipal() override;
+  virtual nsIPrincipal* PartitionedPrincipal() override;
 
   // nsIDOMWindow
   NS_DECL_NSIDOMWINDOW
@@ -1098,7 +1098,7 @@ class nsGlobalWindowOuter final : public mozilla::dom::EventTarget,
 
   nsCOMPtr<nsIPrincipal> mDocumentPrincipal;
   nsCOMPtr<nsIPrincipal> mDocumentStoragePrincipal;
-  nsCOMPtr<nsIPrincipal> mDocumentIntrinsicStoragePrincipal;
+  nsCOMPtr<nsIPrincipal> mDocumentPartitionedPrincipal;
 
 #ifdef DEBUG
   uint32_t mSerial;
diff --git a/dom/base/nsIScriptObjectPrincipal.h b/dom/base/nsIScriptObjectPrincipal.h
index 3752888f877b..3089e8fe4b2e 100644
--- a/dom/base/nsIScriptObjectPrincipal.h
+++ b/dom/base/nsIScriptObjectPrincipal.h
@@ -29,7 +29,7 @@ class nsIScriptObjectPrincipal : public nsISupports {
 
   virtual nsIPrincipal* GetEffectiveStoragePrincipal() = 0;
 
-  virtual nsIPrincipal* IntrinsicStoragePrincipal() = 0;
+  virtual nsIPrincipal* PartitionedPrincipal() = 0;
 };
 
 NS_DEFINE_STATIC_IID_ACCESSOR(nsIScriptObjectPrincipal,
diff --git a/dom/broadcastchannel/BroadcastChannel.cpp b/dom/broadcastchannel/BroadcastChannel.cpp
index af8af46206dc..0b647b5e0aa3 100644
--- a/dom/broadcastchannel/BroadcastChannel.cpp
+++ b/dom/broadcastchannel/BroadcastChannel.cpp
@@ -234,9 +234,7 @@ already_AddRefed<BroadcastChannel> BroadcastChannel::Constructor(
 
     storageAccess = workerPrivate->StorageAccess();
     storagePrincipalInfo = workerPrivate->GetEffectiveStoragePrincipalInfo();
-
-    // TODO This is broken, it will be fixed in the following patches.
-    origin = workerPrivate->PartitionedOrigin();
+    origin = workerPrivate->StoragePrincipalOrigin();
 
     originNoSuffix = workerPrivate->GetLocationInfo().mOrigin;
 
diff --git a/dom/html/nsHTMLDocument.cpp b/dom/html/nsHTMLDocument.cpp
index 0b7d509560c1..56ac241e5549 100644
--- a/dom/html/nsHTMLDocument.cpp
+++ b/dom/html/nsHTMLDocument.cpp
@@ -162,10 +162,10 @@ void nsHTMLDocument::Reset(nsIChannel* aChannel, nsILoadGroup* aLoadGroup) {
 
 void nsHTMLDocument::ResetToURI(nsIURI* aURI, nsILoadGroup* aLoadGroup,
                                 nsIPrincipal* aPrincipal,
-                                nsIPrincipal* aStoragePrincipal) {
+                                nsIPrincipal* aPartitionedPrincipal) {
   mLoadFlags = nsIRequest::LOAD_NORMAL;
 
-  Document::ResetToURI(aURI, aLoadGroup, aPrincipal, aStoragePrincipal);
+  Document::ResetToURI(aURI, aLoadGroup, aPrincipal, aPartitionedPrincipal);
 
   mImages = nullptr;
   mApplets = nullptr;
diff --git a/dom/html/nsHTMLDocument.h b/dom/html/nsHTMLDocument.h
index 7ae59bcff19b..91d783531bf9 100644
--- a/dom/html/nsHTMLDocument.h
+++ b/dom/html/nsHTMLDocument.h
@@ -51,7 +51,7 @@ class nsHTMLDocument : public mozilla::dom::Document {
   virtual void Reset(nsIChannel* aChannel, nsILoadGroup* aLoadGroup) override;
   virtual void ResetToURI(nsIURI* aURI, nsILoadGroup* aLoadGroup,
                           nsIPrincipal* aPrincipal,
-                          nsIPrincipal* aStoragePrincipal) override;
+                          nsIPrincipal* aPartitionedPrincipal) override;
 
   virtual nsresult StartDocumentLoad(const char* aCommand, nsIChannel* aChannel,
                                      nsILoadGroup* aLoadGroup,
diff --git a/dom/interfaces/base/nsIBrowser.idl b/dom/interfaces/base/nsIBrowser.idl
index 300b09e13824..6d8aff9aaccb 100644
--- a/dom/interfaces/base/nsIBrowser.idl
+++ b/dom/interfaces/base/nsIBrowser.idl
@@ -77,7 +77,7 @@ interface nsIBrowser : nsISupports
   readonly attribute nsIWebProgress remoteWebProgressManager;
 
   readonly attribute nsIPrincipal contentPrincipal;
-  readonly attribute nsIPrincipal contentStoragePrincipal;
+  readonly attribute nsIPrincipal contentPartitionedPrincipal;
   readonly attribute nsIPrincipal contentBlockingAllowListPrincipal;
   readonly attribute nsIContentSecurityPolicy csp;
   readonly attribute nsIReferrerInfo referrerInfo;
@@ -133,8 +133,8 @@ interface nsIBrowser : nsISupports
    * @param aDocumentURI the URI of the new document
    * @param aTitle the title of the new doucment
    * @param aContentPrincipal the security principal of the new document
-   * @param aContentStoragePrincipal the security principal for the new
-   *                                 document's storage
+   * @param aContentPartitionedPrincipal the security principal for the new
+   *                                     document's storage
    * @param aCSP the content security policy of the new document
    * @param aReferrerInfo the referrer info of the new document
    * @param aIsSynthetic whether or not the document is synthetic
@@ -151,7 +151,7 @@ interface nsIBrowser : nsISupports
                                in nsIURI aDocumentURI,
                                in AString aTitle,
                                in nsIPrincipal aContentPrincipal,
-                               in nsIPrincipal aContentStoragePrincipal,
+                               in nsIPrincipal aContentPartitionedPrincipal,
                                in nsIContentSecurityPolicy aCSP,
                                in nsIReferrerInfo aReferrerInfo,
                                in boolean aIsSynthetic,
diff --git a/dom/ipc/BrowserChild.cpp b/dom/ipc/BrowserChild.cpp
index 2b17323d8a93..4c900b099396 100644
--- a/dom/ipc/BrowserChild.cpp
+++ b/dom/ipc/BrowserChild.cpp
@@ -3647,8 +3647,8 @@ NS_IMETHODIMP BrowserChild::OnLocationChange(nsIWebProgress* aWebProgress,
         docShell->GetCharsetAutodetected();
 
     locationChangeData->contentPrincipal() = document->NodePrincipal();
-    locationChangeData->contentStoragePrincipal() =
-        document->EffectiveStoragePrincipal();
+    locationChangeData->contentPartitionedPrincipal() =
+        document->PartitionedPrincipal();
     locationChangeData->csp() = document->GetCsp();
     locationChangeData->referrerInfo() = document->ReferrerInfo();
     locationChangeData->isSyntheticDocument() = document->IsSyntheticDocument();
diff --git a/dom/ipc/BrowserParent.cpp b/dom/ipc/BrowserParent.cpp
index f30a1394fe89..9ff5b77702aa 100644
--- a/dom/ipc/BrowserParent.cpp
+++ b/dom/ipc/BrowserParent.cpp
@@ -2692,7 +2692,7 @@ mozilla::ipc::IPCResult BrowserParent::RecvOnLocationChange(
         aLocationChangeData->charsetAutodetected(),
         aLocationChangeData->documentURI(), aLocationChangeData->title(),
         aLocationChangeData->contentPrincipal(),
-        aLocationChangeData->contentStoragePrincipal(),
+        aLocationChangeData->contentPartitionedPrincipal(),
         aLocationChangeData->csp(), aLocationChangeData->referrerInfo(),
         aLocationChangeData->isSyntheticDocument(),
         aWebProgressData->innerDOMWindowID(),
diff --git a/dom/ipc/DOMTypes.ipdlh b/dom/ipc/DOMTypes.ipdlh
index 188ae46a7a7d..5735e83e221f 100644
--- a/dom/ipc/DOMTypes.ipdlh
+++ b/dom/ipc/DOMTypes.ipdlh
@@ -241,7 +241,7 @@ struct DocShellLoadStateInit
   bool InheritPrincipal;
   bool PrincipalIsExplicit;
   nsIPrincipal PrincipalToInherit;
-  nsIPrincipal StoragePrincipalToInherit;
+  nsIPrincipal PartitionedPrincipalToInherit;
   bool ForceAllowDataURI;
   bool OriginalFrameSrc;
   bool IsFormSubmission;
diff --git a/dom/ipc/PBrowser.ipdl b/dom/ipc/PBrowser.ipdl
index 64e40dfa65e1..bd9dcbd20805 100644
--- a/dom/ipc/PBrowser.ipdl
+++ b/dom/ipc/PBrowser.ipdl
@@ -147,7 +147,7 @@ struct WebProgressLocationChangeData
   nsString charset;
   nsIURI documentURI;
   nsIPrincipal contentPrincipal;
-  nsIPrincipal contentStoragePrincipal;
+  nsIPrincipal contentPartitionedPrincipal;
   nsIContentSecurityPolicy csp;
   nsIReferrerInfo referrerInfo;
   uint64_t? requestContextID;
diff --git a/dom/serviceworkers/ServiceWorkerPrivate.cpp b/dom/serviceworkers/ServiceWorkerPrivate.cpp
index a240d0c28397..3bada6c3a9ea 100644
--- a/dom/serviceworkers/ServiceWorkerPrivate.cpp
+++ b/dom/serviceworkers/ServiceWorkerPrivate.cpp
@@ -1705,9 +1705,9 @@ nsresult ServiceWorkerPrivate::SpawnWorkerIfNeeded(WakeUpReason aWhy,
 
   info.mPrincipal = mInfo->Principal();
   info.mLoadingPrincipal = info.mPrincipal;
-  // StoragePrincipal for ServiceWorkers is equal to mPrincipal because, at the
-  // moment, ServiceWorkers are not exposed in partitioned contexts.
-  info.mStoragePrincipal = info.mPrincipal;
+  // PartitionedPrincipal for ServiceWorkers is equal to mPrincipal because, at
+  // the moment, ServiceWorkers are not exposed in partitioned contexts.
+  info.mPartitionedPrincipal = info.mPrincipal;
 
   info.mCookieJarSettings = mozilla::net::CookieJarSettings::Create();
   MOZ_ASSERT(info.mCookieJarSettings);
@@ -1735,7 +1735,7 @@ nsresult ServiceWorkerPrivate::SpawnWorkerIfNeeded(WakeUpReason aWhy,
   WorkerPrivate::OverrideLoadInfoLoadGroup(info, info.mPrincipal);
 
   rv = info.SetPrincipalsAndCSPOnMainThread(
-      info.mPrincipal, info.mStoragePrincipal, info.mLoadGroup, nullptr);
+      info.mPrincipal, info.mPartitionedPrincipal, info.mLoadGroup, nullptr);
   if (NS_WARN_IF(NS_FAILED(rv))) {
     return rv;
   }
diff --git a/dom/serviceworkers/ServiceWorkerPrivateImpl.cpp b/dom/serviceworkers/ServiceWorkerPrivateImpl.cpp
index 69f140aea7fc..b56450359196 100644
--- a/dom/serviceworkers/ServiceWorkerPrivateImpl.cpp
+++ b/dom/serviceworkers/ServiceWorkerPrivateImpl.cpp
@@ -69,7 +69,7 @@ ServiceWorkerPrivateImpl::RAIIActorPtrHolder::~RAIIActorPtrHolder() {
 }
 
 RemoteWorkerControllerChild*
-    ServiceWorkerPrivateImpl::RAIIActorPtrHolder::operator->() const {
+ServiceWorkerPrivateImpl::RAIIActorPtrHolder::operator->() const {
   AssertIsOnMainThread();
 
   return get();
@@ -168,9 +168,10 @@ nsresult ServiceWorkerPrivateImpl::Initialize() {
 
   mRemoteWorkerData.loadingPrincipalInfo() = principalInfo;
   mRemoteWorkerData.principalInfo() = principalInfo;
-  // storagePrincipalInfo for ServiceWorkers is equal to principalInfo because,
-  // at the moment, ServiceWorkers are not exposed in partitioned contexts.
-  mRemoteWorkerData.storagePrincipalInfo() = principalInfo;
+  // partitionedPrincipalInfo for ServiceWorkers is equal to principalInfo
+  // because, at the moment, ServiceWorkers are not exposed in partitioned
+  // contexts.
+  mRemoteWorkerData.partitionedPrincipalInfo() = principalInfo;
 
   rv = uri->GetHost(mRemoteWorkerData.domain());
   NS_ENSURE_SUCCESS(rv, rv);
diff --git a/dom/webidl/Document.webidl b/dom/webidl/Document.webidl
index 8130db018f47..7063e36d899e 100644
--- a/dom/webidl/Document.webidl
+++ b/dom/webidl/Document.webidl
@@ -390,6 +390,13 @@ partial interface Document {
   [ChromeOnly]
   readonly attribute Principal effectiveStoragePrincipal;
 
+  // You should probably not be using this principal getter since it performs
+  // no checks to ensure that the partitioned principal should really be used
+  // here.  It is only designed to be used in very specific circumstances, such
+  // as when inheriting the document/storage principal.
+  [ChromeOnly]
+  readonly attribute Principal partitionedPrincipal;
+
   // The principal to use for the content blocking allow list
   [ChromeOnly]
   readonly attribute Principal? contentBlockingAllowListPrincipal;
diff --git a/dom/workers/ScriptLoader.cpp b/dom/workers/ScriptLoader.cpp
index 9143b0330491..43bb7be2d544 100644
--- a/dom/workers/ScriptLoader.cpp
+++ b/dom/workers/ScriptLoader.cpp
@@ -1430,8 +1430,8 @@ class ScriptLoaderRunnable final : public nsIRunnable, public nsINamed {
       // referrer logic depends on the WorkerPrivate principal having a URL
       // that matches the worker script URL.  If bug 1340694 is ever fixed
       // this can be removed.
-      // XXX: force the storagePrincipal to be equal to the response one. This
-      // is OK for now because we don't want to expose storagePrincipal
+      // XXX: force the partitionedPrincipal to be equal to the response one.
+      // This is OK for now because we don't want to expose partitionedPrincipal
       // functionality in ServiceWorkers yet.
       rv = mWorkerPrivate->SetPrincipalsAndCSPOnMainThread(
           responsePrincipal, responsePrincipal, loadGroup, nullptr);
diff --git a/dom/workers/WorkerLoadInfo.cpp b/dom/workers/WorkerLoadInfo.cpp
index 3cc6439d8f1d..eca09e3b3505 100644
--- a/dom/workers/WorkerLoadInfo.cpp
+++ b/dom/workers/WorkerLoadInfo.cpp
@@ -98,13 +98,13 @@ WorkerLoadInfoData::WorkerLoadInfoData()
       mSecureContext(eNotSet) {}
 
 nsresult WorkerLoadInfo::SetPrincipalsAndCSPOnMainThread(
-    nsIPrincipal* aPrincipal, nsIPrincipal* aStoragePrincipal,
+    nsIPrincipal* aPrincipal, nsIPrincipal* aPartitionedPrincipal,
     nsILoadGroup* aLoadGroup, nsIContentSecurityPolicy* aCsp) {
   AssertIsOnMainThread();
   MOZ_ASSERT(NS_LoadGroupMatchesPrincipal(aLoadGroup, aPrincipal));
 
   mPrincipal = aPrincipal;
-  mStoragePrincipal = aStoragePrincipal;
+  mPartitionedPrincipal = aPartitionedPrincipal;
   mPrincipalIsSystem = aPrincipal->IsSystemPrincipal();
   mPrincipalIsAddonOrExpandedAddon =
       aPrincipal->GetIsAddonOrExpandedAddonPrincipal();
@@ -126,7 +126,7 @@ nsresult WorkerLoadInfo::SetPrincipalsAndCSPOnMainThread(
   mLoadGroup = aLoadGroup;
 
   mPrincipalInfo = MakeUnique<PrincipalInfo>();
-  mStoragePrincipalInfo = MakeUnique<PrincipalInfo>();
+  mPartitionedPrincipalInfo = MakeUnique<PrincipalInfo>();
   StoragePrincipalHelper::GetRegularPrincipalOriginAttributes(
       aLoadGroup, mOriginAttributes);
 
@@ -139,16 +139,16 @@ nsresult WorkerLoadInfo::SetPrincipalsAndCSPOnMainThread(
   rv = aPrincipal->GetOrigin(mOrigin);
   NS_ENSURE_SUCCESS(rv, rv);
 
-  if (aPrincipal->Equals(aStoragePrincipal)) {
-    *mStoragePrincipalInfo = *mPrincipalInfo;
+  if (aPrincipal->Equals(aPartitionedPrincipal)) {
+    *mPartitionedPrincipalInfo = *mPrincipalInfo;
     mPartitionedOrigin = mOrigin;
   } else {
-    mStoragePrincipalInfo = MakeUnique<PrincipalInfo>();
-    rv = PrincipalToPrincipalInfo(aStoragePrincipal,
-                                  mStoragePrincipalInfo.get());
+    mPartitionedPrincipalInfo = MakeUnique<PrincipalInfo>();
+    rv = PrincipalToPrincipalInfo(aPartitionedPrincipal,
+                                  mPartitionedPrincipalInfo.get());
     NS_ENSURE_SUCCESS(rv, rv);
 
-    rv = aStoragePrincipal->GetOrigin(mPartitionedOrigin);
+    rv = aPartitionedPrincipal->GetOrigin(mPartitionedOrigin);
     NS_ENSURE_SUCCESS(rv, rv);
   }
 
@@ -157,11 +157,11 @@ nsresult WorkerLoadInfo::SetPrincipalsAndCSPOnMainThread(
 
 nsresult WorkerLoadInfo::GetPrincipalsAndLoadGroupFromChannel(
     nsIChannel* aChannel, nsIPrincipal** aPrincipalOut,
-    nsIPrincipal** aStoragePrincipalOut, nsILoadGroup** aLoadGroupOut) {
+    nsIPrincipal** aPartitionedPrincipalOut, nsILoadGroup** aLoadGroupOut) {
   AssertIsOnMainThread();
   MOZ_DIAGNOSTIC_ASSERT(aChannel);
   MOZ_DIAGNOSTIC_ASSERT(aPrincipalOut);
-  MOZ_DIAGNOSTIC_ASSERT(aStoragePrincipalOut);
+  MOZ_DIAGNOSTIC_ASSERT(aPartitionedPrincipalOut);
   MOZ_DIAGNOSTIC_ASSERT(aLoadGroupOut);
 
   // Initial triggering principal should be set
@@ -171,10 +171,10 @@ nsresult WorkerLoadInfo::GetPrincipalsAndLoadGroupFromChannel(
   MOZ_DIAGNOSTIC_ASSERT(ssm);
 
   nsCOMPtr<nsIPrincipal> channelPrincipal;
-  nsCOMPtr<nsIPrincipal> channelStoragePrincipal;
+  nsCOMPtr<nsIPrincipal> channelPartitionedPrincipal;
   nsresult rv = ssm->GetChannelResultPrincipals(
       aChannel, getter_AddRefs(channelPrincipal),
-      getter_AddRefs(channelStoragePrincipal));
+      getter_AddRefs(channelPartitionedPrincipal));
   NS_ENSURE_SUCCESS(rv, rv);
 
   // Every time we call GetChannelResultPrincipal() it will return a different
@@ -188,7 +188,7 @@ nsresult WorkerLoadInfo::GetPrincipalsAndLoadGroupFromChannel(
   if (mPrincipal && mPrincipal->GetIsNullPrincipal() &&
       channelPrincipal->GetIsNullPrincipal()) {
     channelPrincipal = mPrincipal;
-    channelStoragePrincipal = mPrincipal;
+    channelPartitionedPrincipal = mPrincipal;
   }
 
   nsCOMPtr<nsILoadGroup> channelLoadGroup;
@@ -221,7 +221,7 @@ nsresult WorkerLoadInfo::GetPrincipalsAndLoadGroupFromChannel(
         // Assign the system principal to the resource:// worker only if it
         // was loaded from code using the system principal.
         channelPrincipal = mLoadingPrincipal;
-        channelStoragePrincipal = mLoadingPrincipal;
+        channelPartitionedPrincipal = mLoadingPrincipal;
       } else {
         return NS_ERROR_DOM_BAD_URI;
       }
@@ -233,7 +233,7 @@ nsresult WorkerLoadInfo::GetPrincipalsAndLoadGroupFromChannel(
   MOZ_ASSERT(NS_LoadGroupMatchesPrincipal(channelLoadGroup, channelPrincipal));
 
   channelPrincipal.forget(aPrincipalOut);
-  channelStoragePrincipal.forget(aStoragePrincipalOut);
+  channelPartitionedPrincipal.forget(aPartitionedPrincipalOut);
   channelLoadGroup.forget(aLoadGroupOut);
 
   return NS_OK;
@@ -243,10 +243,10 @@ nsresult WorkerLoadInfo::SetPrincipalsAndCSPFromChannel(nsIChannel* aChannel) {
   AssertIsOnMainThread();
 
   nsCOMPtr<nsIPrincipal> principal;
-  nsCOMPtr<nsIPrincipal> storagePrincipal;
+  nsCOMPtr<nsIPrincipal> partitionedPrincipal;
   nsCOMPtr<nsILoadGroup> loadGroup;
   nsresult rv = GetPrincipalsAndLoadGroupFromChannel(
-      aChannel, getter_AddRefs(principal), getter_AddRefs(storagePrincipal),
+      aChannel, getter_AddRefs(principal), getter_AddRefs(partitionedPrincipal),
       getter_AddRefs(loadGroup));
   NS_ENSURE_SUCCESS(rv, rv);
 
@@ -257,18 +257,18 @@ nsresult WorkerLoadInfo::SetPrincipalsAndCSPFromChannel(nsIChannel* aChannel) {
     nsCOMPtr<nsILoadInfo> loadinfo = aChannel->LoadInfo();
     csp = loadinfo->GetCsp();
   }
-  return SetPrincipalsAndCSPOnMainThread(principal, storagePrincipal, loadGroup,
-                                         csp);
+  return SetPrincipalsAndCSPOnMainThread(principal, partitionedPrincipal,
+                                         loadGroup, csp);
 }
 
 bool WorkerLoadInfo::FinalChannelPrincipalIsValid(nsIChannel* aChannel) {
   AssertIsOnMainThread();
 
   nsCOMPtr<nsIPrincipal> principal;
-  nsCOMPtr<nsIPrincipal> storagePrincipal;
+  nsCOMPtr<nsIPrincipal> partitionedPrincipal;
   nsCOMPtr<nsILoadGroup> loadGroup;
   nsresult rv = GetPrincipalsAndLoadGroupFromChannel(
-      aChannel, getter_AddRefs(principal), getter_AddRefs(storagePrincipal),
+      aChannel, getter_AddRefs(principal), getter_AddRefs(partitionedPrincipal),
       getter_AddRefs(loadGroup));
   NS_ENSURE_SUCCESS(rv, false);
 
@@ -293,9 +293,9 @@ bool WorkerLoadInfo::PrincipalIsValid() const {
   return mPrincipal && mPrincipalInfo &&
          mPrincipalInfo->type() != PrincipalInfo::T__None &&
          mPrincipalInfo->type() <= PrincipalInfo::T__Last &&
-         mStoragePrincipal && mStoragePrincipalInfo &&
-         mStoragePrincipalInfo->type() != PrincipalInfo::T__None &&
-         mStoragePrincipalInfo->type() <= PrincipalInfo::T__Last;
+         mPartitionedPrincipal && mPartitionedPrincipalInfo &&
+         mPartitionedPrincipalInfo->type() != PrincipalInfo::T__None &&
+         mPartitionedPrincipalInfo->type() <= PrincipalInfo::T__Last;
 }
 
 bool WorkerLoadInfo::PrincipalURIMatchesScriptURL() {
@@ -375,7 +375,7 @@ bool WorkerLoadInfo::ProxyReleaseMainThreadObjects(
   SwapToISupportsArray(mBaseURI, doomed);
   SwapToISupportsArray(mResolvedScriptURI, doomed);
   SwapToISupportsArray(mPrincipal, doomed);
-  SwapToISupportsArray(mStoragePrincipal, doomed);
+  SwapToISupportsArray(mPartitionedPrincipal, doomed);
   SwapToISupportsArray(mLoadingPrincipal, doomed);
   SwapToISupportsArray(mChannel, doomed);
   SwapToISupportsArray(mCSP, doomed);
diff --git a/dom/workers/WorkerLoadInfo.h b/dom/workers/WorkerLoadInfo.h
index 3b3c46e04e41..168e08b5262f 100644
--- a/dom/workers/WorkerLoadInfo.h
+++ b/dom/workers/WorkerLoadInfo.h
@@ -52,7 +52,7 @@ struct WorkerLoadInfoData {
   // If we load a data: URL, mPrincipal will be a null principal.
   nsCOMPtr<nsIPrincipal> mLoadingPrincipal;
   nsCOMPtr<nsIPrincipal> mPrincipal;
-  nsCOMPtr<nsIPrincipal> mStoragePrincipal;
+  nsCOMPtr<nsIPrincipal> mPartitionedPrincipal;
 
   // Taken from the parent context.
   nsCOMPtr<nsICookieJarSettings> mCookieJarSettings;
@@ -102,7 +102,7 @@ struct WorkerLoadInfoData {
   RefPtr<InterfaceRequestor> mInterfaceRequestor;
 
   UniquePtr<mozilla::ipc::PrincipalInfo> mPrincipalInfo;
-  UniquePtr<mozilla::ipc::PrincipalInfo> mStoragePrincipalInfo;
+  UniquePtr<mozilla::ipc::PrincipalInfo> mPartitionedPrincipalInfo;
   nsCString mDomain;
   nsString mOriginNoSuffix;  // Derived from mPrincipal; can be used on worker
                              // thread.
@@ -157,13 +157,13 @@ struct WorkerLoadInfo : WorkerLoadInfoData {
   WorkerLoadInfo& operator=(WorkerLoadInfo&& aOther) = default;
 
   nsresult SetPrincipalsAndCSPOnMainThread(nsIPrincipal* aPrincipal,
-                                           nsIPrincipal* aStoragePrincipal,
+                                           nsIPrincipal* aPartitionedPrincipal,
                                            nsILoadGroup* aLoadGroup,
                                            nsIContentSecurityPolicy* aCSP);
 
   nsresult GetPrincipalsAndLoadGroupFromChannel(
       nsIChannel* aChannel, nsIPrincipal** aPrincipalOut,
-      nsIPrincipal** aStoragePrincipalOut, nsILoadGroup** aLoadGroupOut);
+      nsIPrincipal** aPartitionedPrincipalOut, nsILoadGroup** aLoadGroupOut);
 
   nsresult SetPrincipalsAndCSPFromChannel(nsIChannel* aChannel);
 
diff --git a/dom/workers/WorkerPrivate.cpp b/dom/workers/WorkerPrivate.cpp
index a6f586683a7a..eabfd8c239de 100644
--- a/dom/workers/WorkerPrivate.cpp
+++ b/dom/workers/WorkerPrivate.cpp
@@ -2028,10 +2028,10 @@ void WorkerPrivate::SetBaseURI(nsIURI* aBaseURI) {
 }
 
 nsresult WorkerPrivate::SetPrincipalsAndCSPOnMainThread(
-    nsIPrincipal* aPrincipal, nsIPrincipal* aStoragePrincipal,
+    nsIPrincipal* aPrincipal, nsIPrincipal* aPartitionedPrincipal,
     nsILoadGroup* aLoadGroup, nsIContentSecurityPolicy* aCsp) {
   return mLoadInfo.SetPrincipalsAndCSPOnMainThread(
-      aPrincipal, aStoragePrincipal, aLoadGroup, aCsp);
+      aPrincipal, aPartitionedPrincipal, aLoadGroup, aCsp);
 }
 
 nsresult WorkerPrivate::SetPrincipalsAndCSPFromChannel(nsIChannel* aChannel) {
@@ -5333,6 +5333,23 @@ void WorkerPrivate::EnsureOwnerEmbedderPolicy() {
   }
 }
 
+const mozilla::ipc::PrincipalInfo&
+WorkerPrivate::GetEffectiveStoragePrincipalInfo() const {
+  AssertIsOnWorkerThread();
+
+  if (mLoadInfo.mFirstPartyStorageAccessGranted) {
+    return *mLoadInfo.mPrincipalInfo;
+  }
+
+  // TODO: this is wrong and it will be fixed by the next patch.
+  return *mLoadInfo.mPartitionedPrincipalInfo;
+}
+
+const nsACString& WorkerPrivate::StoragePrincipalOrigin() const {
+  // TODO: this is wrong and it will be fixed by the next patch.
+  return mLoadInfo.mPartitionedOrigin;
+}
+
 NS_IMPL_ADDREF(WorkerPrivate::EventTarget)
 NS_IMPL_RELEASE(WorkerPrivate::EventTarget)
 
diff --git a/dom/workers/WorkerPrivate.h b/dom/workers/WorkerPrivate.h
index ca82b97d3499..7538f7a5d1af 100644
--- a/dom/workers/WorkerPrivate.h
+++ b/dom/workers/WorkerPrivate.h
@@ -694,11 +694,6 @@ class WorkerPrivate : public RelativeTimeline {
     return mLoadInfo.mPrincipal;
   }
 
-  nsIPrincipal* GetEffectiveStoragePrincipal() const {
-    AssertIsOnMainThread();
-    return mLoadInfo.mStoragePrincipal;
-  }
-
   nsIPrincipal* GetLoadingPrincipal() const {
     AssertIsOnMainThread();
     return mLoadInfo.mLoadingPrincipal;
@@ -708,6 +703,8 @@ class WorkerPrivate : public RelativeTimeline {
 
   const nsACString& Origin() const { return mLoadInfo.mOrigin; }
 
+  const nsACString& StoragePrincipalOrigin() const;
+
   const nsACString& PartitionedOrigin() const {
     return mLoadInfo.mPartitionedOrigin;
   }
@@ -726,9 +723,7 @@ class WorkerPrivate : public RelativeTimeline {
     return *mLoadInfo.mPrincipalInfo;
   }
 
-  const mozilla::ipc::PrincipalInfo& GetEffectiveStoragePrincipalInfo() const {
-    return *mLoadInfo.mStoragePrincipalInfo;
-  }
+  const mozilla::ipc::PrincipalInfo& GetEffectiveStoragePrincipalInfo() const;
 
   already_AddRefed<nsIChannel> ForgetWorkerChannel() {
     AssertIsOnMainThread();
@@ -863,7 +858,7 @@ class WorkerPrivate : public RelativeTimeline {
   void CycleCollect(bool aDummy);
 
   nsresult SetPrincipalsAndCSPOnMainThread(nsIPrincipal* aPrincipal,
-                                           nsIPrincipal* aStoragePrincipal,
+                                           nsIPrincipal* aPartitionedPrincipal,
                                            nsILoadGroup* aLoadGroup,
                                            nsIContentSecurityPolicy* aCsp);
 
diff --git a/dom/workers/remoteworkers/RemoteWorkerChild.cpp b/dom/workers/remoteworkers/RemoteWorkerChild.cpp
index ecf6e7ba28f0..1881bacb5710 100644
--- a/dom/workers/remoteworkers/RemoteWorkerChild.cpp
+++ b/dom/workers/remoteworkers/RemoteWorkerChild.cpp
@@ -325,10 +325,10 @@ nsresult RemoteWorkerChild::ExecWorkerOnMainThread(RemoteWorkerData&& aData) {
     return loadingPrincipalOrErr.unwrapErr();
   }
 
-  auto storagePrincipalOrErr =
-      PrincipalInfoToPrincipal(aData.storagePrincipalInfo());
-  if (NS_WARN_IF(storagePrincipalOrErr.isErr())) {
-    return storagePrincipalOrErr.unwrapErr();
+  auto partitionedPrincipalOrErr =
+      PrincipalInfoToPrincipal(aData.partitionedPrincipalInfo());
+  if (NS_WARN_IF(partitionedPrincipalOrErr.isErr())) {
+    return partitionedPrincipalOrErr.unwrapErr();
   }
 
   WorkerLoadInfo info;
@@ -336,13 +336,13 @@ nsresult RemoteWorkerChild::ExecWorkerOnMainThread(RemoteWorkerData&& aData) {
   info.mResolvedScriptURI = DeserializeURI(aData.resolvedScriptURL());
 
   info.mPrincipalInfo = MakeUnique<PrincipalInfo>(aData.principalInfo());
-  info.mStoragePrincipalInfo =
-      MakeUnique<PrincipalInfo>(aData.storagePrincipalInfo());
+  info.mPartitionedPrincipalInfo =
+      MakeUnique<PrincipalInfo>(aData.partitionedPrincipalInfo());
 
   info.mReferrerInfo = aData.referrerInfo();
   info.mDomain = aData.domain();
   info.mPrincipal = principal;
-  info.mStoragePrincipal = storagePrincipalOrErr.unwrap();
+  info.mPartitionedPrincipal = partitionedPrincipalOrErr.unwrap();
   info.mLoadingPrincipal = loadingPrincipalOrErr.unwrap();
   info.mStorageAccess = aData.storageAccess();
   info.mOriginAttributes =
@@ -383,7 +383,7 @@ nsresult RemoteWorkerChild::ExecWorkerOnMainThread(RemoteWorkerData&& aData) {
   }
 
   rv = info.SetPrincipalsAndCSPOnMainThread(
-      info.mPrincipal, info.mStoragePrincipal, info.mLoadGroup, info.mCSP);
+      info.mPrincipal, info.mPartitionedPrincipal, info.mLoadGroup, info.mCSP);
   if (NS_WARN_IF(NS_FAILED(rv))) {
     return rv;
   }
diff --git a/dom/workers/remoteworkers/RemoteWorkerTypes.ipdlh b/dom/workers/remoteworkers/RemoteWorkerTypes.ipdlh
index 8c1030a935e7..ee68bbfd5e4a 100644
--- a/dom/workers/remoteworkers/RemoteWorkerTypes.ipdlh
+++ b/dom/workers/remoteworkers/RemoteWorkerTypes.ipdlh
@@ -49,7 +49,7 @@ struct RemoteWorkerData
 
   PrincipalInfo loadingPrincipalInfo;
   PrincipalInfo principalInfo;
-  PrincipalInfo storagePrincipalInfo;
+  PrincipalInfo partitionedPrincipalInfo;
 
   nsCString domain;
 
diff --git a/dom/workers/sharedworkers/SharedWorker.cpp b/dom/workers/sharedworkers/SharedWorker.cpp
index bb54daff2f96..4e3b91f2bee3 100644
--- a/dom/workers/sharedworkers/SharedWorker.cpp
+++ b/dom/workers/sharedworkers/SharedWorker.cpp
@@ -121,9 +121,9 @@ already_AddRefed<SharedWorker> SharedWorker::Constructor(
     return nullptr;
   }
 
-  // Here, the StoragePrincipal is always equal to the SharedWorker's principal
-  // because the channel is not opened yet, and, because of this, it's not
-  // classified. We need to force the correct originAttributes.
+  // Here, the PartitionedPrincipal is always equal to the SharedWorker's
+  // principal because the channel is not opened yet, and, because of this, it's
+  // not classified. We need to force the correct originAttributes.
   if (ShouldPartitionStorage(storageAllowed)) {
     nsCOMPtr<nsIScriptObjectPrincipal> sop = do_QueryInterface(window);
     if (!sop) {
@@ -137,27 +137,27 @@ already_AddRefed<SharedWorker> SharedWorker::Constructor(
       return nullptr;
     }
 
-    nsIPrincipal* windowStoragePrincipal = sop->GetEffectiveStoragePrincipal();
-    if (!windowStoragePrincipal) {
+    nsIPrincipal* windowPartitionedPrincipal = sop->PartitionedPrincipal();
+    if (!windowPartitionedPrincipal) {
       aRv.Throw(NS_ERROR_UNEXPECTED);
       return nullptr;
     }
 
-    if (!windowPrincipal->Equals(windowStoragePrincipal)) {
-      loadInfo.mStoragePrincipal =
+    if (!windowPrincipal->Equals(windowPartitionedPrincipal)) {
+      loadInfo.mPartitionedPrincipal =
           BasePrincipal::Cast(loadInfo.mPrincipal)
               ->CloneForcingOriginAttributes(
-                  BasePrincipal::Cast(windowStoragePrincipal)
+                  BasePrincipal::Cast(windowPartitionedPrincipal)
                       ->OriginAttributesRef());
     }
   }
 
-  PrincipalInfo storagePrincipalInfo;
-  if (loadInfo.mPrincipal->Equals(loadInfo.mStoragePrincipal)) {
-    storagePrincipalInfo = principalInfo;
+  PrincipalInfo partitionedPrincipalInfo;
+  if (loadInfo.mPrincipal->Equals(loadInfo.mPartitionedPrincipal)) {
+    partitionedPrincipalInfo = principalInfo;
   } else {
-    aRv = PrincipalToPrincipalInfo(loadInfo.mStoragePrincipal,
-                                   &storagePrincipalInfo);
+    aRv = PrincipalToPrincipalInfo(loadInfo.mPartitionedPrincipal,
+                                   &partitionedPrincipalInfo);
     if (NS_WARN_IF(aRv.Failed())) {
       return nullptr;
     }
@@ -195,7 +195,7 @@ already_AddRefed<SharedWorker> SharedWorker::Constructor(
 
   RemoteWorkerData remoteWorkerData(
       nsString(aScriptURL), baseURL, resolvedScriptURL, name,
-      loadingPrincipalInfo, principalInfo, storagePrincipalInfo,
+      loadingPrincipalInfo, principalInfo, partitionedPrincipalInfo,
       loadInfo.mDomain, isSecureContext, ipcClientInfo, loadInfo.mReferrerInfo,
       storageAllowed, void_t() /* OptionalServiceWorkerData */, agentClusterId);
 
diff --git a/dom/workers/sharedworkers/SharedWorkerManager.cpp b/dom/workers/sharedworkers/SharedWorkerManager.cpp
index 82e353fa8bf9..680d5aab456c 100644
--- a/dom/workers/sharedworkers/SharedWorkerManager.cpp
+++ b/dom/workers/sharedworkers/SharedWorkerManager.cpp
@@ -22,12 +22,12 @@ namespace dom {
 already_AddRefed<SharedWorkerManagerHolder> SharedWorkerManager::Create(
     SharedWorkerService* aService, nsIEventTarget* aPBackgroundEventTarget,
     const RemoteWorkerData& aData, nsIPrincipal* aLoadingPrincipal,
-    const OriginAttributes& aStoragePrincipalAttrs) {
+    const OriginAttributes& aPartitionedPrincipalAttrs) {
   MOZ_ASSERT(NS_IsMainThread());
 
   RefPtr<SharedWorkerManager> manager =
       new SharedWorkerManager(aPBackgroundEventTarget, aData, aLoadingPrincipal,
-                              aStoragePrincipalAttrs);
+                              aPartitionedPrincipalAttrs);
 
   RefPtr<SharedWorkerManagerHolder> holder =
       new SharedWorkerManagerHolder(manager, aService);
@@ -37,11 +37,11 @@ already_AddRefed<SharedWorkerManagerHolder> SharedWorkerManager::Create(
 SharedWorkerManager::SharedWorkerManager(
     nsIEventTarget* aPBackgroundEventTarget, const RemoteWorkerData& aData,
     nsIPrincipal* aLoadingPrincipal,
-    const OriginAttributes& aStoragePrincipalAttrs)
+    const OriginAttributes& aPartitionedPrincipalAttrs)
     : mPBackgroundEventTarget(aPBackgroundEventTarget),
       mLoadingPrincipal(aLoadingPrincipal),
       mDomain(aData.domain()),
-      mStoragePrincipalAttrs(aStoragePrincipalAttrs),
+      mPartitionedPrincipalAttrs(aPartitionedPrincipalAttrs),
       mResolvedScriptURL(DeserializeURI(aData.resolvedScriptURL())),
       mName(aData.name()),
       mIsSecureContext(aData.isSecureContext()),
@@ -83,7 +83,7 @@ already_AddRefed<SharedWorkerManagerHolder>
 SharedWorkerManager::MatchOnMainThread(
     SharedWorkerService* aService, const nsACString& aDomain,
     nsIURI* aScriptURL, const nsAString& aName, nsIPrincipal* aLoadingPrincipal,
-    const OriginAttributes& aStoragePrincipalAttrs) {
+    const OriginAttributes& aPartitionedPrincipalAttrs) {
   MOZ_ASSERT(NS_IsMainThread());
 
   bool urlEquals;
@@ -96,7 +96,7 @@ SharedWorkerManager::MatchOnMainThread(
                // SharedWorker's loading principal and vice versa.
                mLoadingPrincipal->Subsumes(aLoadingPrincipal) &&
                aLoadingPrincipal->Subsumes(mLoadingPrincipal) &&
-               mStoragePrincipalAttrs == aStoragePrincipalAttrs;
+               mPartitionedPrincipalAttrs == aPartitionedPrincipalAttrs;
   if (!match) {
     return nullptr;
   }
diff --git a/dom/workers/sharedworkers/SharedWorkerManager.h b/dom/workers/sharedworkers/SharedWorkerManager.h
index 45daddf794c5..556de14a5916 100644
--- a/dom/workers/sharedworkers/SharedWorkerManager.h
+++ b/dom/workers/sharedworkers/SharedWorkerManager.h
@@ -70,7 +70,7 @@ class SharedWorkerManager final : public RemoteWorkerObserver {
   static already_AddRefed<SharedWorkerManagerHolder> Create(
       SharedWorkerService* aService, nsIEventTarget* aPBackgroundEventTarget,
       const RemoteWorkerData& aData, nsIPrincipal* aLoadingPrincipal,
-      const OriginAttributes& aStoragePrincipalAttrs);
+      const OriginAttributes& aPartitionedPrincipalAttrs);
 
   // Returns a holder if this manager matches. The holder blocks the shutdown of
   // the manager.
@@ -78,7 +78,7 @@ class SharedWorkerManager final : public RemoteWorkerObserver {
       SharedWorkerService* aService, const nsACString& aDomain,
       nsIURI* aScriptURL, const nsAString& aName,
       nsIPrincipal* aLoadingPrincipal,
-      const OriginAttributes& aStoragePrincipalAttrs);
+      const OriginAttributes& aPartitionedPrincipalAttrs);
 
   // RemoteWorkerObserver
 
@@ -119,7 +119,7 @@ class SharedWorkerManager final : public RemoteWorkerObserver {
   SharedWorkerManager(nsIEventTarget* aPBackgroundEventTarget,
                       const RemoteWorkerData& aData,
                       nsIPrincipal* aLoadingPrincipal,
-                      const OriginAttributes& aStoragePrincipalAttrs);
+                      const OriginAttributes& aPartitionedPrincipalAttrs);
 
   ~SharedWorkerManager();
 
@@ -127,7 +127,7 @@ class SharedWorkerManager final : public RemoteWorkerObserver {
 
   nsCOMPtr<nsIPrincipal> mLoadingPrincipal;
   const nsCString mDomain;
-  const OriginAttributes mStoragePrincipalAttrs;
+  const OriginAttributes mPartitionedPrincipalAttrs;
   const nsCOMPtr<nsIURI> mResolvedScriptURL;
   const nsString mName;
   const bool mIsSecureContext;
diff --git a/dom/workers/sharedworkers/SharedWorkerService.cpp b/dom/workers/sharedworkers/SharedWorkerService.cpp
index a16d204f3e13..92b143258889 100644
--- a/dom/workers/sharedworkers/SharedWorkerService.cpp
+++ b/dom/workers/sharedworkers/SharedWorkerService.cpp
@@ -166,11 +166,11 @@ void SharedWorkerService::GetOrCreateWorkerManagerOnMainThread(
   MOZ_ASSERT(aBackgroundEventTarget);
   MOZ_ASSERT(aActor);
 
-  auto storagePrincipalOrErr =
-      PrincipalInfoToPrincipal(aData.storagePrincipalInfo());
-  if (NS_WARN_IF(storagePrincipalOrErr.isErr())) {
+  auto partitionedPrincipalOrErr =
+      PrincipalInfoToPrincipal(aData.partitionedPrincipalInfo());
+  if (NS_WARN_IF(partitionedPrincipalOrErr.isErr())) {
     ErrorPropagationOnMainThread(aBackgroundEventTarget, aActor,
-                                 storagePrincipalOrErr.unwrapErr());
+                                 partitionedPrincipalOrErr.unwrapErr());
     return;
   }
 
@@ -185,7 +185,8 @@ void SharedWorkerService::GetOrCreateWorkerManagerOnMainThread(
   RefPtr<SharedWorkerManagerHolder> managerHolder;
 
   nsCOMPtr<nsIPrincipal> loadingPrincipal = loadingPrincipalOrErr.unwrap();
-  nsCOMPtr<nsIPrincipal> storagePrincipal = storagePrincipalOrErr.unwrap();
+  nsCOMPtr<nsIPrincipal> partitionedPrincipal =
+      partitionedPrincipalOrErr.unwrap();
 
   // Let's see if there is already a SharedWorker to share.
   nsCOMPtr<nsIURI> resolvedScriptURL =
@@ -193,7 +194,7 @@ void SharedWorkerService::GetOrCreateWorkerManagerOnMainThread(
   for (SharedWorkerManager* workerManager : mWorkerManagers) {
     managerHolder = workerManager->MatchOnMainThread(
         this, aData.domain(), resolvedScriptURL, aData.name(), loadingPrincipal,
-        BasePrincipal::Cast(storagePrincipal)->OriginAttributesRef());
+        BasePrincipal::Cast(partitionedPrincipal)->OriginAttributesRef());
     if (managerHolder) {
       break;
     }
@@ -203,7 +204,7 @@ void SharedWorkerService::GetOrCreateWorkerManagerOnMainThread(
   if (!managerHolder) {
     managerHolder = SharedWorkerManager::Create(
         this, aBackgroundEventTarget, aData, loadingPrincipal,
-        BasePrincipal::Cast(storagePrincipal)->OriginAttributesRef());
+        BasePrincipal::Cast(partitionedPrincipal)->OriginAttributesRef());
 
     mWorkerManagers.AppendElement(managerHolder->Manager());
   } else {
diff --git a/dom/xml/XMLDocument.cpp b/dom/xml/XMLDocument.cpp
index 3d97b5806863..e736bef4cc74 100644
--- a/dom/xml/XMLDocument.cpp
+++ b/dom/xml/XMLDocument.cpp
@@ -216,14 +216,14 @@ void XMLDocument::Reset(nsIChannel* aChannel, nsILoadGroup* aLoadGroup) {
 
 void XMLDocument::ResetToURI(nsIURI* aURI, nsILoadGroup* aLoadGroup,
                              nsIPrincipal* aPrincipal,
-                             nsIPrincipal* aStoragePrincipal) {
+                             nsIPrincipal* aPartitionedPrincipal) {
   if (mChannelIsPending) {
     StopDocumentLoad();
     mChannel->Cancel(NS_BINDING_ABORTED);
     mChannelIsPending = false;
   }
 
-  Document::ResetToURI(aURI, aLoadGroup, aPrincipal, aStoragePrincipal);
+  Document::ResetToURI(aURI, aLoadGroup, aPrincipal, aPartitionedPrincipal);
 }
 
 void XMLDocument::SetSuppressParserErrorElement(bool aSuppress) {
diff --git a/dom/xml/XMLDocument.h b/dom/xml/XMLDocument.h
index 1af28534b8df..1749a9ca7d77 100644
--- a/dom/xml/XMLDocument.h
+++ b/dom/xml/XMLDocument.h
@@ -27,7 +27,7 @@ class XMLDocument : public Document {
   virtual void Reset(nsIChannel* aChannel, nsILoadGroup* aLoadGroup) override;
   virtual void ResetToURI(nsIURI* aURI, nsILoadGroup* aLoadGroup,
                           nsIPrincipal* aPrincipal,
-                          nsIPrincipal* aStoragePrincipal) override;
+                          nsIPrincipal* aPartitionedPrincipal) override;
 
   virtual void SetSuppressParserErrorElement(bool aSuppress) override;
   virtual bool SuppressParserErrorElement() override;
diff --git a/dom/xslt/base/txURIUtils.cpp b/dom/xslt/base/txURIUtils.cpp
index c4e72805fad8..78dc6b988ca4 100644
--- a/dom/xslt/base/txURIUtils.cpp
+++ b/dom/xslt/base/txURIUtils.cpp
@@ -46,7 +46,7 @@ void URIUtils::resolveHref(const nsAString& href, const nsAString& base,
 void URIUtils::ResetWithSource(Document* aNewDoc, nsINode* aSourceNode) {
   nsCOMPtr<Document> sourceDoc = aSourceNode->OwnerDoc();
   nsIPrincipal* sourcePrincipal = sourceDoc->NodePrincipal();
-  nsIPrincipal* sourceStoragePrincipal = sourceDoc->EffectiveStoragePrincipal();
+  nsIPrincipal* sourcePartitionedPrincipal = sourceDoc->PartitionedPrincipal();
 
   // Copy the channel and loadgroup from the source document.
   nsCOMPtr<nsILoadGroup> loadGroup = sourceDoc->GetDocumentLoadGroup();
@@ -67,7 +67,7 @@ void URIUtils::ResetWithSource(Document* aNewDoc, nsINode* aSourceNode) {
   }
 
   aNewDoc->Reset(channel, loadGroup);
-  aNewDoc->SetPrincipals(sourcePrincipal, sourceStoragePrincipal);
+  aNewDoc->SetPrincipals(sourcePrincipal, sourcePartitionedPrincipal);
   aNewDoc->SetBaseURI(sourceDoc->GetDocBaseURI());
 
   // Inherit the csp if there is one
diff --git a/image/ImageCacheKey.h b/image/ImageCacheKey.h
index b7f311565363..2cc23b6039b8 100644
--- a/image/ImageCacheKey.h
+++ b/image/ImageCacheKey.h
@@ -64,8 +64,8 @@ class ImageCacheKey final {
   static void* GetSpecialCaseDocumentToken(dom::Document* aDocument);
 
   // For anti-tracking we need to use an isolation key. It can be the suffix of
-  // the IntrinsicStoragePrincipal (see StoragePrincipalHelper.h) or the
-  // top-level document's base domain. This is handled by this method.
+  // the PatitionedPrincipal (see StoragePrincipalHelper.h) or the top-level
+  // document's base domain. This is handled by this method.
   static nsCString GetIsolationKey(dom::Document* aDocument, nsIURI* aURI);
 
   void EnsureHash() const;
diff --git a/js/xpconnect/src/BackstagePass.h b/js/xpconnect/src/BackstagePass.h
index a58db3df91ff..7a828b73c8c3 100644
--- a/js/xpconnect/src/BackstagePass.h
+++ b/js/xpconnect/src/BackstagePass.h
@@ -35,9 +35,7 @@ class BackstagePass : public nsIGlobalObject,
     return mPrincipal;
   }
 
-  virtual nsIPrincipal* IntrinsicStoragePrincipal() override {
-    return mPrincipal;
-  }
+  virtual nsIPrincipal* PartitionedPrincipal() override { return mPrincipal; }
 
   JSObject* GetGlobalJSObject() override;
   JSObject* GetGlobalJSObjectPreserveColor() const override;
diff --git a/js/xpconnect/src/SandboxPrivate.h b/js/xpconnect/src/SandboxPrivate.h
index 8db3dc9adc54..a86b8d917072 100644
--- a/js/xpconnect/src/SandboxPrivate.h
+++ b/js/xpconnect/src/SandboxPrivate.h
@@ -46,7 +46,7 @@ class SandboxPrivate : public nsIGlobalObject,
 
   nsIPrincipal* GetEffectiveStoragePrincipal() override { return mPrincipal; }
 
-  nsIPrincipal* IntrinsicStoragePrincipal() override { return mPrincipal; }
+  nsIPrincipal* PartitionedPrincipal() override { return mPrincipal; }
 
   JSObject* GetGlobalJSObject() override { return GetWrapper(); }
   JSObject* GetGlobalJSObjectPreserveColor() const override {
diff --git a/layout/build/nsContentDLF.cpp b/layout/build/nsContentDLF.cpp
index ac8e447491b1..c83f878c207c 100644
--- a/layout/build/nsContentDLF.cpp
+++ b/layout/build/nsContentDLF.cpp
@@ -226,7 +226,7 @@ nsContentDLF::CreateInstanceForDocument(nsISupports* aContainer,
 /* static */
 already_AddRefed<Document> nsContentDLF::CreateBlankDocument(
     nsILoadGroup* aLoadGroup, nsIPrincipal* aPrincipal,
-    nsIPrincipal* aStoragePrincipal, nsDocShell* aContainer) {
+    nsIPrincipal* aPartitionedPrincipal, nsDocShell* aContainer) {
   // create a new blank HTML document
   RefPtr<Document> blankDoc;
   mozilla::Unused << NS_NewHTMLDocument(getter_AddRefs(blankDoc));
@@ -241,7 +241,7 @@ already_AddRefed<Document> nsContentDLF::CreateBlankDocument(
   if (!uri) {
     return nullptr;
   }
-  blankDoc->ResetToURI(uri, aLoadGroup, aPrincipal, aStoragePrincipal);
+  blankDoc->ResetToURI(uri, aLoadGroup, aPrincipal, aPartitionedPrincipal);
   blankDoc->SetContainer(aContainer);
 
   // add some simple content structure
diff --git a/layout/build/nsContentDLF.h b/layout/build/nsContentDLF.h
index 9bc7bd247e95..edcb6b25da90 100644
--- a/layout/build/nsContentDLF.h
+++ b/layout/build/nsContentDLF.h
@@ -46,7 +46,7 @@ class nsContentDLF final : public nsIDocumentLoaderFactory {
    */
   static already_AddRefed<mozilla::dom::Document> CreateBlankDocument(
       nsILoadGroup* aLoadGroup, nsIPrincipal* aPrincipal,
-      nsIPrincipal* aStoragePrincipal, nsDocShell* aContainer);
+      nsIPrincipal* aPartitionedPrincipal, nsDocShell* aContainer);
 
  private:
   static nsresult EnsureUAStyleSheet();
diff --git a/toolkit/components/antitracking/StoragePrincipalHelper.cpp b/toolkit/components/antitracking/StoragePrincipalHelper.cpp
index b7cbd54400d9..b18434599943 100644
--- a/toolkit/components/antitracking/StoragePrincipalHelper.cpp
+++ b/toolkit/components/antitracking/StoragePrincipalHelper.cpp
@@ -17,7 +17,7 @@ namespace mozilla {
 namespace {
 
 bool ChooseOriginAttributes(nsIChannel* aChannel, OriginAttributes& aAttrs,
-                            bool aForceInstrinsicStoragePrincipal) {
+                            bool aForcePartitionedPrincipal) {
   MOZ_ASSERT(aChannel);
 
   nsCOMPtr<nsILoadInfo> loadInfo = aChannel->LoadInfo();
@@ -26,7 +26,7 @@ bool ChooseOriginAttributes(nsIChannel* aChannel, OriginAttributes& aAttrs,
     return false;
   }
 
-  if (!aForceInstrinsicStoragePrincipal) {
+  if (!aForcePartitionedPrincipal) {
     nsCOMPtr<nsIURI> uri;
     nsresult rv = aChannel->GetURI(getter_AddRefs(uri));
     if (NS_FAILED(rv)) {
@@ -80,6 +80,7 @@ bool ChooseOriginAttributes(nsIChannel* aChannel, OriginAttributes& aAttrs,
 // static
 nsresult StoragePrincipalHelper::Create(nsIChannel* aChannel,
                                         nsIPrincipal* aPrincipal,
+                                        bool aForceIsolation,
                                         nsIPrincipal** aStoragePrincipal) {
   MOZ_ASSERT(aChannel);
   MOZ_ASSERT(aPrincipal);
@@ -91,7 +92,7 @@ nsresult StoragePrincipalHelper::Create(nsIChannel* aChannel,
   });
 
   OriginAttributes attrs = aPrincipal->OriginAttributesRef();
-  if (!ChooseOriginAttributes(aChannel, attrs, false)) {
+  if (!ChooseOriginAttributes(aChannel, attrs, aForceIsolation)) {
     return NS_OK;
   }
 
@@ -283,20 +284,7 @@ void StoragePrincipalHelper::GetOriginAttributesForNetworkState(
     return;
   }
 
-  // This part is required because the intrisicStoragePrincipal is not always
-  // partitioned. This should probably change. TODO - bug 1639833.
-  nsCOMPtr<nsICookieJarSettings> cjs = aDocument->CookieJarSettings();
-  MOZ_ASSERT(cjs);
-
-  nsAutoString domain;
-  Unused << cjs->GetFirstPartyDomain(domain);
-
-  if (!domain.IsEmpty()) {
-    aAttributes.SetFirstPartyDomain(false, domain, true /* aForced */);
-    return;
-  }
-
-  aAttributes = aDocument->IntrinsicStoragePrincipal()->OriginAttributesRef();
+  aAttributes = aDocument->PartitionedPrincipal()->OriginAttributesRef();
 }
 
 }  // namespace mozilla
diff --git a/toolkit/components/antitracking/StoragePrincipalHelper.h b/toolkit/components/antitracking/StoragePrincipalHelper.h
index a92bd54a4a19..2c8b886ee72c 100644
--- a/toolkit/components/antitracking/StoragePrincipalHelper.h
+++ b/toolkit/components/antitracking/StoragePrincipalHelper.h
@@ -59,23 +59,27 @@
  * From a Document:
  * - Regular Principal: nsINode::NodePrincipal
  * - Storage Access Principal: Document::EffectiveStoragePrincipal
- * - Partitioned Principal: Document::IntrinsicStoragePrincipal
+ * - Partitioned Principal: Document::PartitionedPrincipal
  *
  * From a Global object:
  * - Regular Principal: nsIScriptObjectPrincipal::GetPrincipal
  * - Storage Access Principal:
  *     nsIScriptObjectPrincipal::GetEffectiveStoragePrincipal
- * - Partitioned Principal: nsIScriptObjectPrincipal::IntrinsicStoragePrincipal
+ * - Partitioned Principal: nsIScriptObjectPrincipal::PartitionedPrincipal
  *
  * From a Worker:
- * - Regular Principal: WorkerPrivate::GetPrincipal
- * - Storage Access Principal: WorkerPrivate::GetEffectiveStoragePrincipal
+ * - Regular Principal: WorkerPrivate::GetPrincipal (main-thread)
+ * - Regular Principal: WorkerPrivate::GetPrincipalInfo (worker thread)
+ * - Storage Access Principal: WorkerPrivate::GetEffectiveStoragePrincipalInfo
+ *                  (worker-thread)
  *
  * For a nsIChannel, the final principals must be calculated and they can be
  * obtained by calling:
  * - Regular Principal: nsIScriptSecurityManager::getChannelResultPrincipal
  * - Storage Access Principal:
  *     nsIScriptSecurityManager::getChannelResultStoragePrincipal
+ * - Partitioned and regular Principal:
+ *     nsIScriptSecurityManager::getChannelResultPrincipals
  *
  * Each use of nsIPrincipal is unique and it should be reviewed by anti-tracking
  * peers. But we can group the use of nsIPrincipal in these categories:
@@ -214,6 +218,7 @@ class OriginAttributes;
 class StoragePrincipalHelper final {
  public:
   static nsresult Create(nsIChannel* aChannel, nsIPrincipal* aPrincipal,
+                         bool aForceIsolation,
                          nsIPrincipal** aStoragePrincipal);
 
   static nsresult PrepareEffectiveStoragePrincipalOriginAttributes(
@@ -229,7 +234,7 @@ class StoragePrincipalHelper final {
 
     // This is a dynamic principal based on the current state of the origin. If
     // the origin has the storage permission granted, effective storagePrincipal
-    // will be the regular principal, otherwise, the intrinsic storagePrincipal
+    // will be the regular principal, otherwise, the partitioned Principal
     // will be used.
     eStorageAccessPrincipal,
 
diff --git a/toolkit/components/sessionstore/SessionStoreUtils.cpp b/toolkit/components/sessionstore/SessionStoreUtils.cpp
index fff955126bf5..7ef35ee80cb4 100644
--- a/toolkit/components/sessionstore/SessionStoreUtils.cpp
+++ b/toolkit/components/sessionstore/SessionStoreUtils.cpp
@@ -1097,7 +1097,7 @@ static void ReadAllEntriesFromStorage(nsPIDOMWindowOuter* aWindow,
     return;
   }
 
-  nsCOMPtr<nsIPrincipal> storagePrincipal = doc->IntrinsicStoragePrincipal();
+  nsCOMPtr<nsIPrincipal> storagePrincipal = doc->EffectiveStoragePrincipal();
   if (!storagePrincipal) {
     return;
   }
diff --git a/toolkit/content/browser-child.js b/toolkit/content/browser-child.js
index ea9a1746f3fa..da1cb33ffdce 100644
--- a/toolkit/content/browser-child.js
+++ b/toolkit/content/browser-child.js
@@ -35,16 +35,16 @@ addMessageListener("BrowserElement:CreateAboutBlank", message => {
   if (!content.document || content.document.documentURI != "about:blank") {
     throw new Error("Can't create a content viewer unless on about:blank");
   }
-  let { principal, storagePrincipal } = message.data;
+  let { principal, partitionedPrincipal } = message.data;
   principal = BrowserUtils.principalWithMatchingOA(
     principal,
     content.document.nodePrincipal
   );
-  storagePrincipal = BrowserUtils.principalWithMatchingOA(
-    storagePrincipal,
-    content.document.effectiveStoragePrincipal
+  partitionedPrincipal = BrowserUtils.principalWithMatchingOA(
+    partitionedPrincipal,
+    content.document.partitionedPrincipal
   );
-  docShell.createAboutBlankContentViewer(principal, storagePrincipal);
+  docShell.createAboutBlankContentViewer(principal, partitionedPrincipal);
 });
 
 // We may not get any responses to Browser:Init if the browser element
diff --git a/toolkit/content/widgets/browser-custom-element.js b/toolkit/content/widgets/browser-custom-element.js
index 9e4e2fe81dd9..7c843b1466cb 100644
--- a/toolkit/content/widgets/browser-custom-element.js
+++ b/toolkit/content/widgets/browser-custom-element.js
@@ -265,7 +265,7 @@
 
       this._contentPrincipal = null;
 
-      this._contentStoragePrincipal = null;
+      this._contentPartitionedPrincipal = null;
 
       this._csp = null;
 
@@ -704,10 +704,10 @@
         : this.contentDocument.nodePrincipal;
     }
 
-    get contentStoragePrincipal() {
+    get contentPartitionedPrincipal() {
       return this.isRemoteBrowser
-        ? this._contentStoragePrincipal
-        : this.contentDocument.effectiveStoragePrincipal;
+        ? this._contentPartitionedPrincipal
+        : this.contentDocument.partitionedPrincipal;
     }
 
     get contentBlockingAllowListPrincipal() {
@@ -1279,7 +1279,7 @@
       aDocumentURI,
       aTitle,
       aContentPrincipal,
-      aContentStoragePrincipal,
+      aContentPartitionedPrincipal,
       aCSP,
       aReferrerInfo,
       aIsSynthetic,
@@ -1302,7 +1302,7 @@
         this._remoteWebNavigation._currentURI = aLocation;
         this._documentURI = aDocumentURI;
         this._contentPrincipal = aContentPrincipal;
-        this._contentStoragePrincipal = aContentStoragePrincipal;
+        this._contentPartitionedPrincipal = aContentPartitionedPrincipal;
         this._csp = aCSP;
         this._referrerInfo = aReferrerInfo;
         this._isSyntheticDocument = aIsSynthetic;
@@ -1333,7 +1333,7 @@
       }
     }
 
-    createAboutBlankContentViewer(aPrincipal, aStoragePrincipal) {
+    createAboutBlankContentViewer(aPrincipal, aPartitionedPrincipal) {
       if (this.isRemoteBrowser) {
         // Ensure that the content process has the permissions which are
         // needed to create a document with the given principal.
@@ -1359,7 +1359,7 @@
         // solution.
         this.messageManager.sendAsyncMessage(
           "BrowserElement:CreateAboutBlank",
-          { principal: aPrincipal, storagePrincipal: aStoragePrincipal }
+          { principal: aPrincipal, partitionedPrincipal: aPartitionedPrincipal }
         );
         return;
       }
@@ -1367,11 +1367,14 @@
         aPrincipal,
         this.contentPrincipal
       );
-      let storagePrincipal = BrowserUtils.principalWithMatchingOA(
-        aStoragePrincipal,
-        this.contentStoragePrincipal
+      let partitionedPrincipal = BrowserUtils.principalWithMatchingOA(
+        aPartitionedPrincipal,
+        this.contentPartitionedPrincipal
+      );
+      this.docShell.createAboutBlankContentViewer(
+        principal,
+        partitionedPrincipal
       );
-      this.docShell.createAboutBlankContentViewer(principal, storagePrincipal);
     }
 
     stopScroll() {
@@ -1699,7 +1702,7 @@
             "_mayEnableCharacterEncodingMenu",
             "_charsetAutodetected",
             "_contentPrincipal",
-            "_contentStoragePrincipal",
+            "_contentPartitionedPrincipal",
             "_isSyntheticDocument",
             "_innerWindowID",
           ]
diff --git a/toolkit/modules/sessionstore/SessionHistory.jsm b/toolkit/modules/sessionstore/SessionHistory.jsm
index 6c16ac331659..d06f7615fdef 100644
--- a/toolkit/modules/sessionstore/SessionHistory.jsm
+++ b/toolkit/modules/sessionstore/SessionHistory.jsm
@@ -270,9 +270,9 @@ var SessionHistoryInternal = {
       );
     }
 
-    if (shEntry.storagePrincipalToInherit) {
-      entry.storagePrincipalToInherit_base64 = E10SUtils.serializePrincipal(
-        shEntry.storagePrincipalToInherit
+    if (shEntry.partitionedPrincipalToInherit) {
+      entry.partitionedPrincipalToInherit_base64 = E10SUtils.serializePrincipal(
+        shEntry.partitionedPrincipalToInherit
       );
     }
 
@@ -551,11 +551,11 @@ var SessionHistoryInternal = {
         return Services.scriptSecurityManager.createNullPrincipal({});
       }
     );
-    // As both storagePrincipal and principalToInherit are both not required to load
+    // As both partitionedPrincipal and principalToInherit are both not required to load
     // it's ok to keep these undefined when we don't have a previously defined principal.
-    if (entry.storagePrincipalToInherit_base64) {
-      shEntry.storagePrincipalToInherit = E10SUtils.deserializePrincipal(
-        entry.storagePrincipalToInherit_base64
+    if (entry.partitionedPrincipalToInherit_base64) {
+      shEntry.partitionedPrincipalToInherit = E10SUtils.deserializePrincipal(
+        entry.partitionedPrincipalToInherit_base64
       );
     }
     if (entry.principalToInherit_base64) {