diff --git a/.eslintrc.js b/.eslintrc.js
index bb9fb8f6fd69..20e952280b6d 100644
--- a/.eslintrc.js
+++ b/.eslintrc.js
@@ -211,12 +211,6 @@ module.exports = {
         ...testPaths.chrome.map(path => `${path}/**/*.js`),
       ],
     },
-    {
-      files: ["netwerk/test/mochitests/**", "netwerk/test/unit*/**"],
-      rules: {
-        "no-shadow": "warn",
-      },
-    },
     {
       // Bug 877389 - Gradually migrate from Cu.reportError to console.error.
       // Enable these as we fix more areas.
diff --git a/netwerk/test/unit/head_trr.js b/netwerk/test/unit/head_trr.js
index 44ea71f38155..ec8c335fa51a 100644
--- a/netwerk/test/unit/head_trr.js
+++ b/netwerk/test/unit/head_trr.js
@@ -361,7 +361,7 @@ function trrQueryHandler(req, resp, url) {
     resp.end("Unexpected method");
   }
 
-  function processRequest(req, resp, payload) {
+  function processRequest(req1, resp1, payload) {
     let dnsQuery = global.dnsPacket.decode(payload);
     let domain = dnsQuery.questions[0].name;
     let type = dnsQuery.questions[0].type;
@@ -387,24 +387,24 @@ function trrQueryHandler(req, resp, url) {
       additionals: response.additionals || [],
     });
 
-    let writeResponse = (resp, buf, context) => {
+    let writeResponse = (resp2, buf2, context) => {
       try {
         if (context.error) {
           // If the error is a valid HTTP response number just write it out.
           if (context.error < 600) {
-            resp.writeHead(context.error);
-            resp.end("Intentional error");
+            resp2.writeHead(context.error);
+            resp2.end("Intentional error");
             return;
           }
 
           // Bigger error means force close the session
-          req.stream.session.close();
+          req1.stream.session.close();
           return;
         }
-        resp.setHeader("Content-Length", buf.length);
-        resp.writeHead(200, { "Content-Type": "application/dns-message" });
-        resp.write(buf);
-        resp.end("");
+        resp2.setHeader("Content-Length", buf2.length);
+        resp2.writeHead(200, { "Content-Type": "application/dns-message" });
+        resp2.write(buf2);
+        resp2.end("");
       } catch (e) {}
     };
 
@@ -417,12 +417,12 @@ function trrQueryHandler(req, resp, url) {
           writeResponse(arg[0], arg[1], arg[2]);
         },
         response.delay,
-        [resp, buf, response]
+        [resp1, buf, response]
       );
       return;
     }
 
-    writeResponse(resp, buf, response);
+    writeResponse(resp1, buf, response);
   }
 }
 
diff --git a/netwerk/test/unit/test_backgroundfilesaver.js b/netwerk/test/unit/test_backgroundfilesaver.js
index af99acb2b461..eeceab9bf8ff 100644
--- a/netwerk/test/unit/test_backgroundfilesaver.js
+++ b/netwerk/test/unit/test_backgroundfilesaver.js
@@ -134,12 +134,12 @@ function promiseVerifyContents(aFile, aExpectedContents) {
 function promiseSaverComplete(aSaver, aOnTargetChangeFn) {
   return new Promise((resolve, reject) => {
     aSaver.observer = {
-      onTargetChange: function BFSO_onSaveComplete(aSaver, aTarget) {
+      onTargetChange: function BFSO_onSaveComplete(saver, aTarget) {
         if (aOnTargetChangeFn) {
           aOnTargetChangeFn(aTarget);
         }
       },
-      onSaveComplete: function BFSO_onSaveComplete(aSaver, aStatus) {
+      onSaveComplete: function BFSO_onSaveComplete(saver, aStatus) {
         if (Components.isSuccessCode(aStatus)) {
           resolve();
         } else {
diff --git a/netwerk/test/unit/test_cache2-01d-basic-not-wanted.js b/netwerk/test/unit/test_cache2-01d-basic-not-wanted.js
index a9dc5ef93c89..9d2b3f8458ff 100644
--- a/netwerk/test/unit/test_cache2-01d-basic-not-wanted.js
+++ b/netwerk/test/unit/test_cache2-01d-basic-not-wanted.js
@@ -9,28 +9,28 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "a1m", "a1d", function (entry) {
+    new OpenCallback(NEW, "a1m", "a1d", function () {
       // Open for read and check
       asyncOpenCacheEntry(
         "http://a/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "a1m", "a1d", function (entry) {
+        new OpenCallback(NORMAL, "a1m", "a1d", function () {
           // Open but don't want the entry
           asyncOpenCacheEntry(
             "http://a/",
             "disk",
             Ci.nsICacheStorage.OPEN_NORMALLY,
             null,
-            new OpenCallback(NOTWANTED, "a1m", "a1d", function (entry) {
+            new OpenCallback(NOTWANTED, "a1m", "a1d", function () {
               // Open for read again and check the entry is OK
               asyncOpenCacheEntry(
                 "http://a/",
                 "disk",
                 Ci.nsICacheStorage.OPEN_NORMALLY,
                 null,
-                new OpenCallback(NORMAL, "a1m", "a1d", function (entry) {
+                new OpenCallback(NORMAL, "a1m", "a1d", function () {
                   finish_cache2_test();
                 })
               );
diff --git a/netwerk/test/unit/test_cache2-01e-basic-bypass-if-busy.js b/netwerk/test/unit/test_cache2-01e-basic-bypass-if-busy.js
index dd6cdf3d5a6e..e77e7afdfca7 100644
--- a/netwerk/test/unit/test_cache2-01e-basic-bypass-if-busy.js
+++ b/netwerk/test/unit/test_cache2-01e-basic-bypass-if-busy.js
@@ -9,7 +9,7 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW | DONTFILL, "a1m", "a1d", function (entry) {
+    new OpenCallback(NEW | DONTFILL, "a1m", "a1d", function () {
       var bypassed = false;
 
       // Open and bypass
@@ -18,7 +18,7 @@ function run_test() {
         "disk",
         Ci.nsICacheStorage.OPEN_BYPASS_IF_BUSY,
         null,
-        new OpenCallback(NOTFOUND, "", "", function (entry) {
+        new OpenCallback(NOTFOUND, "", "", function () {
           Assert.ok(!bypassed);
           bypassed = true;
         })
diff --git a/netwerk/test/unit/test_cache2-02-open-non-existing.js b/netwerk/test/unit/test_cache2-02-open-non-existing.js
index c824bf33a378..2ee0efa68731 100644
--- a/netwerk/test/unit/test_cache2-02-open-non-existing.js
+++ b/netwerk/test/unit/test_cache2-02-open-non-existing.js
@@ -9,28 +9,28 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_READONLY,
     null,
-    new OpenCallback(NOTFOUND, null, null, function (entry) {
+    new OpenCallback(NOTFOUND, null, null, function () {
       // Open the same non-existing for read again, should fail second time
       asyncOpenCacheEntry(
         "http://b/",
         "disk",
         Ci.nsICacheStorage.OPEN_READONLY,
         null,
-        new OpenCallback(NOTFOUND, null, null, function (entry) {
+        new OpenCallback(NOTFOUND, null, null, function () {
           // Try it again normally, should go
           asyncOpenCacheEntry(
             "http://b/",
             "disk",
             Ci.nsICacheStorage.OPEN_NORMALLY,
             null,
-            new OpenCallback(NEW, "b1m", "b1d", function (entry) {
+            new OpenCallback(NEW, "b1m", "b1d", function () {
               // ...and check
               asyncOpenCacheEntry(
                 "http://b/",
                 "disk",
                 Ci.nsICacheStorage.OPEN_NORMALLY,
                 null,
-                new OpenCallback(NORMAL, "b1m", "b1d", function (entry) {
+                new OpenCallback(NORMAL, "b1m", "b1d", function () {
                   finish_cache2_test();
                 })
               );
diff --git a/netwerk/test/unit/test_cache2-03-oncacheentryavail-throws.js b/netwerk/test/unit/test_cache2-03-oncacheentryavail-throws.js
index 92753dc7f366..2b1e230b1a23 100644
--- a/netwerk/test/unit/test_cache2-03-oncacheentryavail-throws.js
+++ b/netwerk/test/unit/test_cache2-03-oncacheentryavail-throws.js
@@ -9,21 +9,21 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW | THROWAVAIL, null, null, function (entry) {
+    new OpenCallback(NEW | THROWAVAIL, null, null, function () {
       // Try it again, should go
       asyncOpenCacheEntry(
         "http://c/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NEW, "c1m", "c1d", function (entry) {
+        new OpenCallback(NEW, "c1m", "c1d", function () {
           // ...and check
           asyncOpenCacheEntry(
             "http://c/",
             "disk",
             Ci.nsICacheStorage.OPEN_NORMALLY,
             null,
-            new OpenCallback(false, "c1m", "c1d", function (entry) {
+            new OpenCallback(false, "c1m", "c1d", function () {
               finish_cache2_test();
             })
           );
diff --git a/netwerk/test/unit/test_cache2-04-oncacheentryavail-throws2x.js b/netwerk/test/unit/test_cache2-04-oncacheentryavail-throws2x.js
index dce2b483ffb5..aea4cfdbf395 100644
--- a/netwerk/test/unit/test_cache2-04-oncacheentryavail-throws2x.js
+++ b/netwerk/test/unit/test_cache2-04-oncacheentryavail-throws2x.js
@@ -9,28 +9,28 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW | THROWAVAIL, null, null, function (entry) {
+    new OpenCallback(NEW | THROWAVAIL, null, null, function () {
       // Open but let OCEA throw ones again
       asyncOpenCacheEntry(
         "http://d/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NEW | THROWAVAIL, null, null, function (entry) {
+        new OpenCallback(NEW | THROWAVAIL, null, null, function () {
           // Try it again, should go
           asyncOpenCacheEntry(
             "http://d/",
             "disk",
             Ci.nsICacheStorage.OPEN_NORMALLY,
             null,
-            new OpenCallback(NEW, "d1m", "d1d", function (entry) {
+            new OpenCallback(NEW, "d1m", "d1d", function () {
               // ...and check
               asyncOpenCacheEntry(
                 "http://d/",
                 "disk",
                 Ci.nsICacheStorage.OPEN_NORMALLY,
                 null,
-                new OpenCallback(NORMAL, "d1m", "d1d", function (entry) {
+                new OpenCallback(NORMAL, "d1m", "d1d", function () {
                   finish_cache2_test();
                 })
               );
diff --git a/netwerk/test/unit/test_cache2-05-visit.js b/netwerk/test/unit/test_cache2-05-visit.js
index 7ed9b9effd5d..b4ed3ea26ee5 100644
--- a/netwerk/test/unit/test_cache2-05-visit.js
+++ b/netwerk/test/unit/test_cache2-05-visit.js
@@ -42,13 +42,13 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "a1m", "a1d", function (entry) {
+    new OpenCallback(NEW, "a1m", "a1d", function () {
       asyncOpenCacheEntry(
         "http://a/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "a1m", "a1d", function (entry) {
+        new OpenCallback(NORMAL, "a1m", "a1d", function () {
           mc.fired();
         })
       );
@@ -60,13 +60,13 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "b1m", "b1d", function (entry) {
+    new OpenCallback(NEW, "b1m", "b1d", function () {
       asyncOpenCacheEntry(
         "http://b/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "b1m", "b1d", function (entry) {
+        new OpenCallback(NORMAL, "b1m", "b1d", function () {
           mc.fired();
         })
       );
@@ -78,13 +78,13 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "c1m", "c1d", function (entry) {
+    new OpenCallback(NEW, "c1m", "c1d", function () {
       asyncOpenCacheEntry(
         "http://c/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "c1m", "c1d", function (entry) {
+        new OpenCallback(NORMAL, "c1m", "c1d", function () {
           mc.fired();
         })
       );
@@ -96,13 +96,13 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "d1m", "d1d", function (entry) {
+    new OpenCallback(NEW, "d1m", "d1d", function () {
       asyncOpenCacheEntry(
         "http://d/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "d1m", "d1d", function (entry) {
+        new OpenCallback(NORMAL, "d1m", "d1d", function () {
           mc.fired();
         })
       );
diff --git a/netwerk/test/unit/test_cache2-06-pb-mode.js b/netwerk/test/unit/test_cache2-06-pb-mode.js
index 376eba22a220..ddece342768f 100644
--- a/netwerk/test/unit/test_cache2-06-pb-mode.js
+++ b/netwerk/test/unit/test_cache2-06-pb-mode.js
@@ -13,13 +13,13 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     Services.loadContextInfo.private,
-    new OpenCallback(NEW, "p1m", "p1d", function (entry) {
+    new OpenCallback(NEW, "p1m", "p1d", function () {
       asyncOpenCacheEntry(
         "http://p1/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         Services.loadContextInfo.private,
-        new OpenCallback(NORMAL, "p1m", "p1d", function (entry) {
+        new OpenCallback(NORMAL, "p1m", "p1d", function () {
           // Check it's there
           syncWithCacheIOThread(function () {
             var storage = getCacheStorage(
diff --git a/netwerk/test/unit/test_cache2-07-visit-memory.js b/netwerk/test/unit/test_cache2-07-visit-memory.js
index c3c56ee4cc79..11f0f6a2e7f3 100644
--- a/netwerk/test/unit/test_cache2-07-visit-memory.js
+++ b/netwerk/test/unit/test_cache2-07-visit-memory.js
@@ -34,13 +34,13 @@ function run_test() {
     "memory",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "m1m", "m1d", function (entry) {
+    new OpenCallback(NEW, "m1m", "m1d", function () {
       asyncOpenCacheEntry(
         "http://mem1/",
         "memory",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "m1m", "m1d", function (entry) {
+        new OpenCallback(NORMAL, "m1m", "m1d", function () {
           mc.fired();
         })
       );
@@ -52,13 +52,13 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "a1m", "a1d", function (entry) {
+    new OpenCallback(NEW, "a1m", "a1d", function () {
       asyncOpenCacheEntry(
         "http://a/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "a1m", "a1d", function (entry) {
+        new OpenCallback(NORMAL, "a1m", "a1d", function () {
           mc.fired();
         })
       );
@@ -70,13 +70,13 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "a1m", "a1d", function (entry) {
+    new OpenCallback(NEW, "a1m", "a1d", function () {
       asyncOpenCacheEntry(
         "http://b/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "a1m", "a1d", function (entry) {
+        new OpenCallback(NORMAL, "a1m", "a1d", function () {
           mc.fired();
         })
       );
@@ -88,13 +88,13 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "a1m", "a1d", function (entry) {
+    new OpenCallback(NEW, "a1m", "a1d", function () {
       asyncOpenCacheEntry(
         "http://c/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "a1m", "a1d", function (entry) {
+        new OpenCallback(NORMAL, "a1m", "a1d", function () {
           mc.fired();
         })
       );
@@ -106,13 +106,13 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "a1m", "a1d", function (entry) {
+    new OpenCallback(NEW, "a1m", "a1d", function () {
       asyncOpenCacheEntry(
         "http://d/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "a1m", "a1d", function (entry) {
+        new OpenCallback(NORMAL, "a1m", "a1d", function () {
           mc.fired();
         })
       );
diff --git a/netwerk/test/unit/test_cache2-09-evict-disk-by-uri.js b/netwerk/test/unit/test_cache2-09-evict-disk-by-uri.js
index ea2a4ae7759e..5b9caa9cfb87 100644
--- a/netwerk/test/unit/test_cache2-09-evict-disk-by-uri.js
+++ b/netwerk/test/unit/test_cache2-09-evict-disk-by-uri.js
@@ -8,13 +8,13 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "a1m", "a1d", function (entry) {
+    new OpenCallback(NEW, "a1m", "a1d", function () {
       asyncOpenCacheEntry(
         "http://a/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "a1m", "a1d", function (entry) {
+        new OpenCallback(NORMAL, "a1m", "a1d", function () {
           var storage = getCacheStorage("disk");
           storage.asyncDoomURI(
             createURI("http://a/"),
diff --git a/netwerk/test/unit/test_cache2-10-evict-direct.js b/netwerk/test/unit/test_cache2-10-evict-direct.js
index 1e3689e904bd..dc278e17d4f1 100644
--- a/netwerk/test/unit/test_cache2-10-evict-direct.js
+++ b/netwerk/test/unit/test_cache2-10-evict-direct.js
@@ -8,7 +8,7 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "b1m", "b1d", function (entry) {
+    new OpenCallback(NEW, "b1m", "b1d", function () {
       asyncOpenCacheEntry(
         "http://b/",
         "disk",
diff --git a/netwerk/test/unit/test_cache2-11-evict-memory.js b/netwerk/test/unit/test_cache2-11-evict-memory.js
index ee4790c66102..b73bf2f5cc70 100644
--- a/netwerk/test/unit/test_cache2-11-evict-memory.js
+++ b/netwerk/test/unit/test_cache2-11-evict-memory.js
@@ -3,17 +3,17 @@
 function run_test() {
   do_get_profile();
 
-  var storage = getCacheStorage("memory");
+  var memoryStorage = getCacheStorage("memory");
   var mc = new MultipleCallbacks(3, function () {
-    storage.asyncEvictStorage(
+    memoryStorage.asyncEvictStorage(
       new EvictionCallback(true, function () {
-        storage.asyncVisitStorage(
+        memoryStorage.asyncVisitStorage(
           new VisitCallback(0, 0, [], function () {
-            var storage = getCacheStorage("disk");
+            var diskStorage = getCacheStorage("disk");
 
             var expectedConsumption = 2048;
 
-            storage.asyncVisitStorage(
+            diskStorage.asyncVisitStorage(
               new VisitCallback(
                 2,
                 expectedConsumption,
@@ -36,13 +36,13 @@ function run_test() {
     "memory",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "m2m", "m2d", function (entry) {
+    new OpenCallback(NEW, "m2m", "m2d", function () {
       asyncOpenCacheEntry(
         "http://mem1/",
         "memory",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "m2m", "m2d", function (entry) {
+        new OpenCallback(NORMAL, "m2m", "m2d", function () {
           mc.fired();
         })
       );
@@ -54,13 +54,13 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "a1m", "a1d", function (entry) {
+    new OpenCallback(NEW, "a1m", "a1d", function () {
       asyncOpenCacheEntry(
         "http://a/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "a1m", "a1d", function (entry) {
+        new OpenCallback(NORMAL, "a1m", "a1d", function () {
           mc.fired();
         })
       );
@@ -72,13 +72,13 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "a1m", "a1d", function (entry) {
+    new OpenCallback(NEW, "a1m", "a1d", function () {
       asyncOpenCacheEntry(
         "http://b/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "a1m", "a1d", function (entry) {
+        new OpenCallback(NORMAL, "a1m", "a1d", function () {
           mc.fired();
         })
       );
diff --git a/netwerk/test/unit/test_cache2-12-evict-disk.js b/netwerk/test/unit/test_cache2-12-evict-disk.js
index 9fb9a9441655..6b0d31a27b2a 100644
--- a/netwerk/test/unit/test_cache2-12-evict-disk.js
+++ b/netwerk/test/unit/test_cache2-12-evict-disk.js
@@ -4,13 +4,13 @@ function run_test() {
   do_get_profile();
 
   var mc = new MultipleCallbacks(3, function () {
-    var storage = getCacheStorage("disk");
-    storage.asyncEvictStorage(
+    var diskStorage = getCacheStorage("disk");
+    diskStorage.asyncEvictStorage(
       new EvictionCallback(true, function () {
-        storage.asyncVisitStorage(
+        diskStorage.asyncVisitStorage(
           new VisitCallback(0, 0, [], function () {
-            var storage = getCacheStorage("memory");
-            storage.asyncVisitStorage(
+            var memoryStorage = getCacheStorage("memory");
+            memoryStorage.asyncVisitStorage(
               new VisitCallback(0, 0, [], function () {
                 finish_cache2_test();
               }),
@@ -28,13 +28,13 @@ function run_test() {
     "memory",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "m2m", "m2d", function (entry) {
+    new OpenCallback(NEW, "m2m", "m2d", function () {
       asyncOpenCacheEntry(
         "http://mem1/",
         "memory",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "m2m", "m2d", function (entry) {
+        new OpenCallback(NORMAL, "m2m", "m2d", function () {
           mc.fired();
         })
       );
@@ -46,13 +46,13 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "a1m", "a1d", function (entry) {
+    new OpenCallback(NEW, "a1m", "a1d", function () {
       asyncOpenCacheEntry(
         "http://a/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "a1m", "a1d", function (entry) {
+        new OpenCallback(NORMAL, "a1m", "a1d", function () {
           mc.fired();
         })
       );
@@ -64,13 +64,13 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "b1m", "b1d", function (entry) {
+    new OpenCallback(NEW, "b1m", "b1d", function () {
       asyncOpenCacheEntry(
         "http://b/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "b1m", "b1d", function (entry) {
+        new OpenCallback(NORMAL, "b1m", "b1d", function () {
           mc.fired();
         })
       );
diff --git a/netwerk/test/unit/test_cache2-15-conditional-304.js b/netwerk/test/unit/test_cache2-15-conditional-304.js
index 2964150628a1..7b672e69a23a 100644
--- a/netwerk/test/unit/test_cache2-15-conditional-304.js
+++ b/netwerk/test/unit/test_cache2-15-conditional-304.js
@@ -9,7 +9,7 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "31m", "31d", function (entry) {
+    new OpenCallback(NEW, "31m", "31d", function () {
       // Open normally but wait for validation from the server
       asyncOpenCacheEntry(
         "http://304/",
diff --git a/netwerk/test/unit/test_cache2-16-conditional-200.js b/netwerk/test/unit/test_cache2-16-conditional-200.js
index 5dd4af7ae8d4..beaa3f0dae2a 100644
--- a/netwerk/test/unit/test_cache2-16-conditional-200.js
+++ b/netwerk/test/unit/test_cache2-16-conditional-200.js
@@ -9,13 +9,13 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "21m", "21d", function (entry) {
+    new OpenCallback(NEW, "21m", "21d", function () {
       asyncOpenCacheEntry(
         "http://200/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "21m", "21d", function (entry) {
+        new OpenCallback(NORMAL, "21m", "21d", function () {
           // Open normally but wait for validation from the server
           asyncOpenCacheEntry(
             "http://200/",
diff --git a/netwerk/test/unit/test_cache2-18-not-valid.js b/netwerk/test/unit/test_cache2-18-not-valid.js
index 64459557e07c..8cbe37be4a56 100644
--- a/netwerk/test/unit/test_cache2-18-not-valid.js
+++ b/netwerk/test/unit/test_cache2-18-not-valid.js
@@ -11,21 +11,21 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW | DOOMED, "v1m", "v1d", function (entry) {
+    new OpenCallback(NEW | DOOMED, "v1m", "v1d", function () {
       // Open for rewrite (don't validate), write different meta and data
       asyncOpenCacheEntry(
         "http://nv/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NOTVALID | RECREATE, "v2m", "v2d", function (entry) {
+        new OpenCallback(NOTVALID | RECREATE, "v2m", "v2d", function () {
           // And check...
           asyncOpenCacheEntry(
             "http://nv/",
             "disk",
             Ci.nsICacheStorage.OPEN_NORMALLY,
             null,
-            new OpenCallback(NORMAL, "v2m", "v2d", function (entry) {
+            new OpenCallback(NORMAL, "v2m", "v2d", function () {
               finish_cache2_test();
             })
           );
diff --git a/netwerk/test/unit/test_cache2-19-range-206.js b/netwerk/test/unit/test_cache2-19-range-206.js
index ece438b00e41..f3f94919324e 100644
--- a/netwerk/test/unit/test_cache2-19-range-206.js
+++ b/netwerk/test/unit/test_cache2-19-range-206.js
@@ -9,7 +9,7 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "206m", "206part1-", function (entry) {
+    new OpenCallback(NEW, "206m", "206part1-", function () {
       // Open normally but wait for validation from the server
       asyncOpenCacheEntry(
         "http://r206/",
@@ -22,8 +22,8 @@ function run_test() {
             NEW | WAITFORWRITE | PARTIAL,
             "206m",
             "-part2",
-            function (entry) {
-              entry.setValid();
+            function (entry1) {
+              entry1.setValid();
             }
           ).onCacheEntryAvailable(entry, true, Cr.NS_OK);
         })
diff --git a/netwerk/test/unit/test_cache2-20-range-200.js b/netwerk/test/unit/test_cache2-20-range-200.js
index 0bd929a67523..31b8223c358a 100644
--- a/netwerk/test/unit/test_cache2-20-range-200.js
+++ b/netwerk/test/unit/test_cache2-20-range-200.js
@@ -9,7 +9,7 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "200m1", "200part1a-", function (entry) {
+    new OpenCallback(NEW, "200m1", "200part1a-", function () {
       // Open normally but wait for validation from the server
       asyncOpenCacheEntry(
         "http://r200/",
@@ -23,8 +23,8 @@ function run_test() {
             NEW | WAITFORWRITE | RECREATE,
             "200m2",
             "200part1b--part2b",
-            function (entry) {
-              entry.setValid();
+            function (entry1) {
+              entry1.setValid();
             }
           ).onCacheEntryAvailable(entry, true, Cr.NS_OK);
         })
diff --git a/netwerk/test/unit/test_cache2-21-anon-storage.js b/netwerk/test/unit/test_cache2-21-anon-storage.js
index c84ca0ff770e..1db0047475e2 100644
--- a/netwerk/test/unit/test_cache2-21-anon-storage.js
+++ b/netwerk/test/unit/test_cache2-21-anon-storage.js
@@ -9,33 +9,33 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     Services.loadContextInfo.anonymous,
-    new OpenCallback(NEW, "an1", "an1", function (entry) {
+    new OpenCallback(NEW, "an1", "an1", function () {
       asyncOpenCacheEntry(
         "http://anon1/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         Services.loadContextInfo.anonymous,
-        new OpenCallback(NORMAL, "an1", "an1", function (entry) {
+        new OpenCallback(NORMAL, "an1", "an1", function () {
           // Create and check an entry non-anon disk storage
           asyncOpenCacheEntry(
             "http://anon1/",
             "disk",
             Ci.nsICacheStorage.OPEN_NORMALLY,
             Services.loadContextInfo.default,
-            new OpenCallback(NEW, "na1", "na1", function (entry) {
+            new OpenCallback(NEW, "na1", "na1", function () {
               asyncOpenCacheEntry(
                 "http://anon1/",
                 "disk",
                 Ci.nsICacheStorage.OPEN_NORMALLY,
                 Services.loadContextInfo.default,
-                new OpenCallback(NORMAL, "na1", "na1", function (entry) {
+                new OpenCallback(NORMAL, "na1", "na1", function () {
                   // check the anon entry is still there and intact
                   asyncOpenCacheEntry(
                     "http://anon1/",
                     "disk",
                     Ci.nsICacheStorage.OPEN_NORMALLY,
                     Services.loadContextInfo.anonymous,
-                    new OpenCallback(NORMAL, "an1", "an1", function (entry) {
+                    new OpenCallback(NORMAL, "an1", "an1", function () {
                       finish_cache2_test();
                     })
                   );
diff --git a/netwerk/test/unit/test_cache2-25-chunk-memory-limit.js b/netwerk/test/unit/test_cache2-25-chunk-memory-limit.js
index cbad8918ad75..8c5a383ba60d 100644
--- a/netwerk/test/unit/test_cache2-25-chunk-memory-limit.js
+++ b/netwerk/test/unit/test_cache2-25-chunk-memory-limit.js
@@ -36,9 +36,9 @@ function run_test() {
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        function (status, entry) {
-          Assert.equal(status, Cr.NS_OK);
-          var oStr2 = entry.openOutputStream(0, data.length);
+        function (status1, entry1) {
+          Assert.equal(status1, Cr.NS_OK);
+          var oStr2 = entry1.openOutputStream(0, data.length);
           do_check_throws_nsIException(
             () => oStr2.write(data, data.length),
             "NS_ERROR_OUT_OF_MEMORY"
diff --git a/netwerk/test/unit/test_cache2-26-no-outputstream-open.js b/netwerk/test/unit/test_cache2-26-no-outputstream-open.js
index dbcd699d6738..bdb116436c1a 100644
--- a/netwerk/test/unit/test_cache2-26-no-outputstream-open.js
+++ b/netwerk/test/unit/test_cache2-26-no-outputstream-open.js
@@ -13,7 +13,7 @@ function run_test() {
       NEW | METAONLY | DONTSETVALID | WAITFORWRITE,
       "meta",
       "",
-      function (entry) {
+      function () {
         // Open again, we must get the callback and zero-length data
         executeSoon(() => {
           Cu.forceGC(); // invokes OnHandleClosed on the entry
@@ -23,7 +23,7 @@ function run_test() {
             "disk",
             Ci.nsICacheStorage.OPEN_NORMALLY,
             null,
-            new OpenCallback(NORMAL, "meta", "", function (entry) {
+            new OpenCallback(NORMAL, "meta", "", function () {
               finish_cache2_test();
             })
           );
diff --git a/netwerk/test/unit/test_cache2-28-last-access-attrs.js b/netwerk/test/unit/test_cache2-28-last-access-attrs.js
index 2cae81873657..7450e1998f00 100644
--- a/netwerk/test/unit/test_cache2-28-last-access-attrs.js
+++ b/netwerk/test/unit/test_cache2-28-last-access-attrs.js
@@ -29,11 +29,11 @@ function run_test() {
           "disk",
           Ci.nsICacheStorage.OPEN_NORMALLY,
           null,
-          new OpenCallback(NORMAL, "m", "d", function (entry) {
+          new OpenCallback(NORMAL, "m", "d", function (entry1) {
             var secondOpen = NowSeconds();
-            Assert.equal(entry.fetchCount, 2);
-            do_check_time(entry.lastFetched, firstOpen, secondOpen);
-            do_check_time(entry.lastModified, timeStart, firstOpen);
+            Assert.equal(entry1.fetchCount, 2);
+            do_check_time(entry1.lastFetched, firstOpen, secondOpen);
+            do_check_time(entry1.lastModified, timeStart, firstOpen);
 
             finish_cache2_test();
           })
diff --git a/netwerk/test/unit/test_cache2-28a-OPEN_SECRETLY.js b/netwerk/test/unit/test_cache2-28a-OPEN_SECRETLY.js
index f25477f714f6..d30e13af2212 100644
--- a/netwerk/test/unit/test_cache2-28a-OPEN_SECRETLY.js
+++ b/netwerk/test/unit/test_cache2-28a-OPEN_SECRETLY.js
@@ -26,10 +26,10 @@ function run_test() {
           "disk",
           Ci.nsICacheStorage.OPEN_SECRETLY,
           null,
-          new OpenCallback(NORMAL, "m", "d", function (entry) {
-            Assert.equal(entry.fetchCount, 1);
-            do_check_time(entry.lastFetched, now1);
-            do_check_time(entry.lastModified, now1);
+          new OpenCallback(NORMAL, "m", "d", function (entry1) {
+            Assert.equal(entry1.fetchCount, 1);
+            do_check_time(entry1.lastFetched, now1);
+            do_check_time(entry1.lastModified, now1);
 
             finish_cache2_test();
           })
diff --git a/netwerk/test/unit/test_cache2-30a-entry-pinning.js b/netwerk/test/unit/test_cache2-30a-entry-pinning.js
index a63503c266f9..b2541cbf86d4 100644
--- a/netwerk/test/unit/test_cache2-30a-entry-pinning.js
+++ b/netwerk/test/unit/test_cache2-30a-entry-pinning.js
@@ -9,14 +9,14 @@ function run_test() {
     "pin",
     Ci.nsICacheStorage.OPEN_TRUNCATE,
     Services.loadContextInfo.default,
-    new OpenCallback(NEW | WAITFORWRITE, "a1m", "a1d", function (entry) {
+    new OpenCallback(NEW | WAITFORWRITE, "a1m", "a1d", function () {
       // Open for read and check
       asyncOpenCacheEntry(
         "http://a/",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         Services.loadContextInfo.default,
-        new OpenCallback(NORMAL, "a1m", "a1d", function (entry) {
+        new OpenCallback(NORMAL, "a1m", "a1d", function () {
           // Now clear the whole cache
           Services.cache2.clear();
 
@@ -26,7 +26,7 @@ function run_test() {
             "disk",
             Ci.nsICacheStorage.OPEN_NORMALLY,
             Services.loadContextInfo.default,
-            new OpenCallback(NORMAL, "a1m", "a1d", function (entry) {
+            new OpenCallback(NORMAL, "a1m", "a1d", function () {
               finish_cache2_test();
             })
           );
diff --git a/netwerk/test/unit/test_cache2-30b-pinning-storage-clear.js b/netwerk/test/unit/test_cache2-30b-pinning-storage-clear.js
index 86708da82847..21f7f02e4525 100644
--- a/netwerk/test/unit/test_cache2-30b-pinning-storage-clear.js
+++ b/netwerk/test/unit/test_cache2-30b-pinning-storage-clear.js
@@ -11,7 +11,7 @@ function run_test() {
     "pin",
     Ci.nsICacheStorage.OPEN_TRUNCATE,
     lci,
-    new OpenCallback(NEW | WAITFORWRITE, "a1m", "a1d", function (entry) {
+    new OpenCallback(NEW | WAITFORWRITE, "a1m", "a1d", function () {
       // Now clear the disk storage, that should leave the pinned  entry in the cache
       var diskStorage = getCacheStorage("disk", lci);
       diskStorage.asyncEvictStorage(null);
@@ -22,7 +22,7 @@ function run_test() {
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         lci,
-        new OpenCallback(NORMAL, "a1m", "a1d", function (entry) {
+        new OpenCallback(NORMAL, "a1m", "a1d", function () {
           // Now clear the pinning storage, entry should be gone
           var pinningStorage = getCacheStorage("pin", lci);
           pinningStorage.asyncEvictStorage(null);
@@ -32,7 +32,7 @@ function run_test() {
             "disk",
             Ci.nsICacheStorage.OPEN_NORMALLY,
             lci,
-            new OpenCallback(NEW, "", "", function (entry) {
+            new OpenCallback(NEW, "", "", function () {
               finish_cache2_test();
             })
           );
diff --git a/netwerk/test/unit/test_cache2-31-visit-all.js b/netwerk/test/unit/test_cache2-31-visit-all.js
index 481916afcc34..3fed10881f00 100644
--- a/netwerk/test/unit/test_cache2-31-visit-all.js
+++ b/netwerk/test/unit/test_cache2-31-visit-all.js
@@ -52,13 +52,13 @@ function run_test() {
       "disk",
       Ci.nsICacheStorage.OPEN_NORMALLY,
       lcis[i],
-      new OpenCallback(NEW, "a1m", "a1d", function (entry) {
+      new OpenCallback(NEW, "a1m", "a1d", function () {
         asyncOpenCacheEntry(
           "http://a/",
           "disk",
           Ci.nsICacheStorage.OPEN_NORMALLY,
           lcis[i],
-          new OpenCallback(NORMAL, "a1m", "a1d", function (entry) {
+          new OpenCallback(NORMAL, "a1m", "a1d", function () {
             mc.fired();
           })
         );
@@ -70,13 +70,13 @@ function run_test() {
       "disk",
       Ci.nsICacheStorage.OPEN_NORMALLY,
       lcis[i],
-      new OpenCallback(NEW, "b1m", "b1d", function (entry) {
+      new OpenCallback(NEW, "b1m", "b1d", function () {
         asyncOpenCacheEntry(
           "http://b/",
           "disk",
           Ci.nsICacheStorage.OPEN_NORMALLY,
           lcis[i],
-          new OpenCallback(NORMAL, "b1m", "b1d", function (entry) {
+          new OpenCallback(NORMAL, "b1m", "b1d", function () {
             mc.fired();
           })
         );
diff --git a/netwerk/test/unit/test_cache2-32-clear-origin.js b/netwerk/test/unit/test_cache2-32-clear-origin.js
index 8358f2f04521..2234ccd13d56 100644
--- a/netwerk/test/unit/test_cache2-32-clear-origin.js
+++ b/netwerk/test/unit/test_cache2-32-clear-origin.js
@@ -11,25 +11,25 @@ function run_test() {
     "disk",
     Ci.nsICacheStorage.OPEN_NORMALLY,
     null,
-    new OpenCallback(NEW, "e1m", "e1d", function (entry) {
+    new OpenCallback(NEW, "e1m", "e1d", function () {
       asyncOpenCacheEntry(
         URL + "/a",
         "disk",
         Ci.nsICacheStorage.OPEN_NORMALLY,
         null,
-        new OpenCallback(NORMAL, "e1m", "e1d", function (entry) {
+        new OpenCallback(NORMAL, "e1m", "e1d", function () {
           asyncOpenCacheEntry(
             URL2 + "/a",
             "disk",
             Ci.nsICacheStorage.OPEN_NORMALLY,
             null,
-            new OpenCallback(NEW, "f1m", "f1d", function (entry) {
+            new OpenCallback(NEW, "f1m", "f1d", function () {
               asyncOpenCacheEntry(
                 URL2 + "/a",
                 "disk",
                 Ci.nsICacheStorage.OPEN_NORMALLY,
                 null,
-                new OpenCallback(NORMAL, "f1m", "f1d", function (entry) {
+                new OpenCallback(NORMAL, "f1m", "f1d", function () {
                   var url = Services.io.newURI(URL);
                   var principal =
                     Services.scriptSecurityManager.createContentPrincipal(
@@ -44,15 +44,13 @@ function run_test() {
                     "disk",
                     Ci.nsICacheStorage.OPEN_NORMALLY,
                     null,
-                    new OpenCallback(NEW, "e1m", "e1d", function (entry) {
+                    new OpenCallback(NEW, "e1m", "e1d", function () {
                       asyncOpenCacheEntry(
                         URL2 + "/a",
                         "disk",
                         Ci.nsICacheStorage.OPEN_NORMALLY,
                         null,
-                        new OpenCallback(NORMAL, "f1m", "f1d", function (
-                          entry
-                        ) {
+                        new OpenCallback(NORMAL, "f1m", "f1d", function () {
                           finish_cache2_test();
                         })
                       );
diff --git a/netwerk/test/unit/test_cookies_read.js b/netwerk/test/unit/test_cookies_read.js
index d3cc32956451..e7e9e84b3e8e 100644
--- a/netwerk/test/unit/test_cookies_read.js
+++ b/netwerk/test/unit/test_cookies_read.js
@@ -38,7 +38,7 @@ add_task(async () => {
     contentPolicyType: Ci.nsIContentPolicy.TYPE_DOCUMENT,
   });
   for (let i = 0; i < CMAX; ++i) {
-    let uri = NetUtil.newURI("http://" + i + ".com/");
+    uri = NetUtil.newURI("http://" + i + ".com/");
     Services.cookies.setCookieStringFromHttp(
       uri,
       "oh=hai; max-age=1000",
diff --git a/netwerk/test/unit/test_dns_disable_ipv4.js b/netwerk/test/unit/test_dns_disable_ipv4.js
index 48a97f2399a1..286964341e79 100644
--- a/netwerk/test/unit/test_dns_disable_ipv4.js
+++ b/netwerk/test/unit/test_dns_disable_ipv4.js
@@ -14,8 +14,8 @@ const defaultOriginAttributes = {};
 add_task(async function test_none() {
   let [, inRecord] = await new Promise(resolve => {
     let listener = {
-      onLookupComplete(inRequest, inRecord, inStatus) {
-        resolve([inRequest, inRecord, inStatus]);
+      onLookupComplete(inRequest, inRecord1, inStatus) {
+        resolve([inRequest, inRecord1, inStatus]);
       },
       QueryInterface: ChromeUtils.generateQI(["nsIDNSListener"]),
     };
@@ -45,8 +45,8 @@ add_task(async function test_some() {
   gOverride.addIPOverride("example.org", "::1:2:3");
   let [, inRecord] = await new Promise(resolve => {
     let listener = {
-      onLookupComplete(inRequest, inRecord, inStatus) {
-        resolve([inRequest, inRecord, inStatus]);
+      onLookupComplete(inRequest, inRecord1, inStatus) {
+        resolve([inRequest, inRecord1, inStatus]);
       },
       QueryInterface: ChromeUtils.generateQI(["nsIDNSListener"]),
     };
diff --git a/netwerk/test/unit/test_dns_service.js b/netwerk/test/unit/test_dns_service.js
index c2a2d8b8ad1d..22dedd05409c 100644
--- a/netwerk/test/unit/test_dns_service.js
+++ b/netwerk/test/unit/test_dns_service.js
@@ -102,8 +102,8 @@ add_task(
         mainThread,
         defaultOriginAttributes
       );
-      let [, , inStatus] = await listener;
-      Assert.equal(inStatus, Cr.NS_ERROR_UNKNOWN_HOST);
+      let [, , inStatus1] = await listener;
+      Assert.equal(inStatus1, Cr.NS_ERROR_UNKNOWN_HOST);
     } else {
       Assert.throws(
         () => {
diff --git a/netwerk/test/unit/test_doomentry.js b/netwerk/test/unit/test_doomentry.js
index 2ad0ee5525aa..07e17a10807b 100644
--- a/netwerk/test/unit/test_doomentry.js
+++ b/netwerk/test/unit/test_doomentry.js
@@ -65,7 +65,7 @@ function check_doom2(status) {
     "disk",
     Ci.nsICacheStorage.OPEN_TRUNCATE,
     null,
-    function (status, entry) {
+    function (stat, entry) {
       write_entry2(entry, entry.openOutputStream(0, -1));
     }
   );
diff --git a/netwerk/test/unit/test_http2-proxy.js b/netwerk/test/unit/test_http2-proxy.js
index 5dbdb0262a4f..d8aa0019fef1 100644
--- a/netwerk/test/unit/test_http2-proxy.js
+++ b/netwerk/test/unit/test_http2-proxy.js
@@ -352,11 +352,11 @@ add_task(async function setup() {
   processId = await NodeServer.fork();
   await NodeServer.execute(processId, `serverPort = ${server_port}`);
   await NodeServer.execute(processId, http2ProxyCode);
-  let proxy = await NodeServer.execute(
+  let newProxy = await NodeServer.execute(
     processId,
     `http2ProxyCode.startNewProxy()`
   );
-  proxy_port = proxy.port;
+  proxy_port = newProxy.port;
   Assert.notEqual(proxy_port, null);
 
   Services.prefs.setStringPref(
diff --git a/netwerk/test/unit/test_immutable.js b/netwerk/test/unit/test_immutable.js
index 7f45e57e50cf..f2b07c7114ea 100644
--- a/netwerk/test/unit/test_immutable.js
+++ b/netwerk/test/unit/test_immutable.js
@@ -43,7 +43,7 @@ function resetPrefs() {
   prefs.clearUserPref("network.dns.localDomains");
 }
 
-function makeChan(origin, path) {
+function makeChan(path) {
   return NetUtil.newChannel({
     uri: origin + path,
     loadUsingSystemPrincipal: true,
@@ -99,7 +99,7 @@ function doTest1() {
   dump("execute doTest1 - resource without immutable. initial request\n");
   do_test_pending();
   expectConditional = false;
-  var chan = makeChan(origin, "/immutable-test-without-attribute");
+  var chan = makeChan("/immutable-test-without-attribute");
   var listener = new Listener();
   nextTest = doTest2;
   chan.asyncOpen(listener);
@@ -109,7 +109,7 @@ function doTest2() {
   dump("execute doTest2 - resource without immutable. reload\n");
   do_test_pending();
   expectConditional = true;
-  var chan = makeChan(origin, "/immutable-test-without-attribute");
+  var chan = makeChan("/immutable-test-without-attribute");
   var listener = new Listener();
   nextTest = doTest3;
   chan.loadFlags = Ci.nsIRequest.VALIDATE_ALWAYS;
@@ -120,7 +120,7 @@ function doTest3() {
   dump("execute doTest3 - resource without immutable. shift reload\n");
   do_test_pending();
   expectConditional = false;
-  var chan = makeChan(origin, "/immutable-test-without-attribute");
+  var chan = makeChan("/immutable-test-without-attribute");
   var listener = new Listener();
   nextTest = doTest4;
   chan.loadFlags = Ci.nsIRequest.LOAD_BYPASS_CACHE;
@@ -131,7 +131,7 @@ function doTest4() {
   dump("execute doTest4 - resource with immutable. initial request\n");
   do_test_pending();
   expectConditional = false;
-  var chan = makeChan(origin, "/immutable-test-with-attribute");
+  var chan = makeChan("/immutable-test-with-attribute");
   var listener = new Listener();
   nextTest = doTest5;
   chan.asyncOpen(listener);
@@ -141,7 +141,7 @@ function doTest5() {
   dump("execute doTest5 - resource with immutable. reload\n");
   do_test_pending();
   expectConditional = false;
-  var chan = makeChan(origin, "/immutable-test-with-attribute");
+  var chan = makeChan("/immutable-test-with-attribute");
   var listener = new Listener();
   nextTest = doTest6;
   chan.loadFlags = Ci.nsIRequest.VALIDATE_ALWAYS;
@@ -152,7 +152,7 @@ function doTest6() {
   dump("execute doTest6 - resource with immutable. shift reload\n");
   do_test_pending();
   expectConditional = false;
-  var chan = makeChan(origin, "/immutable-test-with-attribute");
+  var chan = makeChan("/immutable-test-with-attribute");
   var listener = new Listener();
   nextTest = doTest7;
   chan.loadFlags = Ci.nsIRequest.LOAD_BYPASS_CACHE;
@@ -163,7 +163,7 @@ function doTest7() {
   dump("execute doTest7 - expired resource with immutable. initial request\n");
   do_test_pending();
   expectConditional = false;
-  var chan = makeChan(origin, "/immutable-test-expired-with-Expires-header");
+  var chan = makeChan("/immutable-test-expired-with-Expires-header");
   var listener = new Listener();
   nextTest = doTest8;
   chan.asyncOpen(listener);
@@ -173,7 +173,7 @@ function doTest8() {
   dump("execute doTest8 - expired resource with immutable. reload\n");
   do_test_pending();
   expectConditional = true;
-  var chan = makeChan(origin, "/immutable-test-expired-with-Expires-header");
+  var chan = makeChan("/immutable-test-expired-with-Expires-header");
   var listener = new Listener();
   nextTest = doTest9;
   chan.loadFlags = Ci.nsIRequest.VALIDATE_ALWAYS;
@@ -186,10 +186,7 @@ function doTest9() {
   );
   do_test_pending();
   expectConditional = false;
-  var chan = makeChan(
-    origin,
-    "/immutable-test-expired-with-last-modified-header"
-  );
+  var chan = makeChan("/immutable-test-expired-with-last-modified-header");
   var listener = new Listener();
   nextTest = doTest10;
   chan.asyncOpen(listener);
@@ -201,10 +198,7 @@ function doTest10() {
   );
   do_test_pending();
   expectConditional = true;
-  var chan = makeChan(
-    origin,
-    "/immutable-test-expired-with-last-modified-header"
-  );
+  var chan = makeChan("/immutable-test-expired-with-last-modified-header");
   var listener = new Listener();
   nextTest = testsDone;
   chan.loadFlags = Ci.nsIRequest.VALIDATE_ALWAYS;
diff --git a/netwerk/test/unit/test_multipart_streamconv_empty.js b/netwerk/test/unit/test_multipart_streamconv_empty.js
index 68bc5e6be804..3d3f9dc85907 100644
--- a/netwerk/test/unit/test_multipart_streamconv_empty.js
+++ b/netwerk/test/unit/test_multipart_streamconv_empty.js
@@ -44,8 +44,8 @@ add_task(async function test_empty() {
         }
       },
 
-      onStopRequest(request, status) {
-        resolve([status, this._buffer]);
+      onStopRequest(request, status1) {
+        resolve([status1, this._buffer]);
       },
     };
     let conv = streamConv.asyncConvertData(
diff --git a/netwerk/test/unit/test_network_connectivity_service.js b/netwerk/test/unit/test_network_connectivity_service.js
index 971b01f0dbc3..6774e79e3407 100644
--- a/netwerk/test/unit/test_network_connectivity_service.js
+++ b/netwerk/test/unit/test_network_connectivity_service.js
@@ -11,10 +11,10 @@ const { HttpServer } = ChromeUtils.importESModule(
 /**
  * Waits for an observer notification to fire.
  *
- * @param {String} topic The notification topic.
+ * @param {String} topicName The notification topic.
  * @returns {Promise} A promise that fulfills when the notification is fired.
  */
-function promiseObserverNotification(topic, matchFunc) {
+function promiseObserverNotification(topicName, matchFunc) {
   return new Promise((resolve, reject) => {
     Services.obs.addObserver(function observe(subject, topic, data) {
       let matches = typeof matchFunc != "function" || matchFunc(subject, data);
@@ -23,7 +23,7 @@ function promiseObserverNotification(topic, matchFunc) {
       }
       Services.obs.removeObserver(observe, topic);
       resolve({ subject, data });
-    }, topic);
+    }, topicName);
   });
 }
 
diff --git a/netwerk/test/unit/test_ntlm_authentication.js b/netwerk/test/unit/test_ntlm_authentication.js
index 6afa55769238..f17f7ebf7d52 100644
--- a/netwerk/test/unit/test_ntlm_authentication.js
+++ b/netwerk/test/unit/test_ntlm_authentication.js
@@ -260,7 +260,7 @@ add_task(async function test_ntlm() {
   chan.notificationCallbacks = new Requestor(FLAG_RETURN_FALSE, 2);
   let [req, buf] = await new Promise(resolve => {
     chan.asyncOpen(
-      new ChannelListener((req, buf) => resolve([req, buf]), null)
+      new ChannelListener((req1, buf1) => resolve([req1, buf1]), null)
     );
   });
   Assert.ok(buf);
diff --git a/netwerk/test/unit/test_predictor.js b/netwerk/test/unit/test_predictor.js
index 491a729d4a93..dce86ce5e0ec 100644
--- a/netwerk/test/unit/test_predictor.js
+++ b/netwerk/test/unit/test_predictor.js
@@ -492,9 +492,9 @@ function continue_test_origin() {
         origin_attributes
       );
       do_timeout(0, () => {
-        var origin = extract_origin(sruri);
-        if (!preconns.includes(origin)) {
-          preconns.push(origin);
+        var origin1 = extract_origin(sruri);
+        if (!preconns.includes(origin1)) {
+          preconns.push(origin1);
         }
 
         sruri = newURI(subresources[2]);
@@ -505,9 +505,9 @@ function continue_test_origin() {
           origin_attributes
         );
         do_timeout(0, () => {
-          var origin = extract_origin(sruri);
-          if (!preconns.includes(origin)) {
-            preconns.push(origin);
+          var origin2 = extract_origin(sruri);
+          if (!preconns.includes(origin2)) {
+            preconns.push(origin2);
           }
 
           var loaduri = newURI("http://localhost:4444/anotherpage.html");
@@ -708,9 +708,9 @@ function test_visitor_doom() {
         console.debug("asyncDoomURI", aURI.spec);
         let doomTask = Promise.all(
           storages.map(storage => {
-            return new Promise(resolve => {
+            return new Promise(resolve1 => {
               storage.asyncDoomURI(aURI, aIdEnhance, {
-                onCacheEntryDoomed: resolve,
+                onCacheEntryDoomed: resolve1,
               });
             });
           })
diff --git a/netwerk/test/unit/test_private_necko_channel.js b/netwerk/test/unit/test_private_necko_channel.js
index a9f0dda280e9..dc6a73e14591 100644
--- a/netwerk/test/unit/test_private_necko_channel.js
+++ b/netwerk/test/unit/test_private_necko_channel.js
@@ -51,8 +51,8 @@ function checkRequest(request, data, context) {
     get_device_entry_count(
       "disk",
       Services.loadContextInfo.private,
-      function (count) {
-        Assert.equal(count, 1);
+      function (count1) {
+        Assert.equal(count1, 1);
         httpserver.stop(do_test_finished);
       }
     );
diff --git a/netwerk/test/unit/test_proxy-slow-upload.js b/netwerk/test/unit/test_proxy-slow-upload.js
index 4bfbe56f10b7..1a406890e155 100644
--- a/netwerk/test/unit/test_proxy-slow-upload.js
+++ b/netwerk/test/unit/test_proxy-slow-upload.js
@@ -83,7 +83,7 @@ add_task(async function test_slow_upload() {
         let { req, buff } = await new Promise(resolve => {
           chan.asyncOpen(
             new ChannelListener(
-              (req, buff) => resolve({ req, buff }),
+              (req1, buff1) => resolve({ req: req1, buff: buff1 }),
               null,
               CL_ALLOW_UNKNOWN_CL
             )
diff --git a/netwerk/test/unit/test_proxyconnect.js b/netwerk/test/unit/test_proxyconnect.js
index a22bb25b312d..7015b3bffba5 100644
--- a/netwerk/test/unit/test_proxyconnect.js
+++ b/netwerk/test/unit/test_proxyconnect.js
@@ -234,7 +234,7 @@ function makeChan(url) {
   return chan;
 }
 
-function socketAccepted(socket, transport) {
+function socketAccepted(socket1, transport) {
   accepted = true;
 
   // copied from httpd.js
@@ -266,7 +266,7 @@ function socketAccepted(socket, transport) {
   }
 }
 
-function stopListening(socket, status) {
+function stopListening() {
   if (tests && tests.length !== 0 && do_throw) {
     do_throw("should never stop");
   }
diff --git a/netwerk/test/unit/test_servers.js b/netwerk/test/unit/test_servers.js
index ce0ca3208996..1aee369f5c50 100644
--- a/netwerk/test/unit/test_servers.js
+++ b/netwerk/test/unit/test_servers.js
@@ -22,7 +22,7 @@ function makeChan(uri) {
   return chan;
 }
 
-function channelOpenPromise(chan, flags, observer) {
+function channelOpenPromise(chan, flags) {
   return new Promise(resolve => {
     function finish(req, buffer) {
       resolve([req, buffer]);
@@ -31,6 +31,20 @@ function channelOpenPromise(chan, flags, observer) {
   });
 }
 
+function registerSimplePathHandler(server, path) {
+  return server.registerPathHandler(path, (req, resp) => {
+    resp.writeHead(200);
+    resp.end("done");
+  });
+}
+
+function regiisterServerNamePathHandler(server, path) {
+  return server.registerPathHandler(path, (req, resp) => {
+    resp.writeHead(200);
+    resp.end(global.server_name);
+  });
+}
+
 add_task(async function test_dual_stack() {
   let httpserv = new HttpServer();
   let content = "ok";
@@ -62,10 +76,7 @@ add_task(async function test_http() {
   });
   equal(req.status, Cr.NS_OK);
   equal(req.QueryInterface(Ci.nsIHttpChannel).responseStatus, 404);
-  await server.registerPathHandler("/test", (req, resp) => {
-    resp.writeHead(200);
-    resp.end("done");
-  });
+  await registerSimplePathHandler(server, "/test");
   chan = makeChan(`http://localhost:${server.port()}/test`);
   req = await new Promise(resolve => {
     chan.asyncOpen(new ChannelListener(resolve, null, CL_ALLOW_UNKNOWN_CL));
@@ -95,10 +106,7 @@ add_task(async function test_https() {
   });
   equal(req.status, Cr.NS_OK);
   equal(req.QueryInterface(Ci.nsIHttpChannel).responseStatus, 404);
-  await server.registerPathHandler("/test", (req, resp) => {
-    resp.writeHead(200);
-    resp.end("done");
-  });
+  await registerSimplePathHandler(server, "/test");
   chan = makeChan(`https://localhost:${server.port()}/test`);
   req = await new Promise(resolve => {
     chan.asyncOpen(new ChannelListener(resolve, null, CL_ALLOW_UNKNOWN_CL));
@@ -127,10 +135,7 @@ add_task(async function test_http2() {
   });
   equal(req.status, Cr.NS_OK);
   equal(req.QueryInterface(Ci.nsIHttpChannel).responseStatus, 404);
-  await server.registerPathHandler("/test", (req, resp) => {
-    resp.writeHead(200);
-    resp.end("done");
-  });
+  await registerSimplePathHandler(server, "/test");
   chan = makeChan(`https://localhost:${server.port()}/test`);
   req = await new Promise(resolve => {
     chan.asyncOpen(new ChannelListener(resolve, null, CL_ALLOW_UNKNOWN_CL));
@@ -167,27 +172,18 @@ add_task(async function test_http1_proxy() {
       await server.execute(
         `global.server_name = "${server.constructor.name}";`
       );
-      await server.registerPathHandler("/test", (req, resp) => {
-        resp.writeHead(200);
-        resp.end(global.server_name);
-      });
-      let chan = makeChan(`${server.origin()}/test`);
-      let { req, buff } = await new Promise(resolve => {
-        chan.asyncOpen(
-          new ChannelListener(
-            (req, buff) => resolve({ req, buff }),
-            null,
-            CL_ALLOW_UNKNOWN_CL
-          )
-        );
-      });
-      equal(req.status, Cr.NS_OK);
-      equal(req.QueryInterface(Ci.nsIHttpChannel).responseStatus, 200);
+      await regiisterServerNamePathHandler(server, "/test");
+      let [req1, buff] = await channelOpenPromise(
+        makeChan(`${server.origin()}/test`),
+        CL_ALLOW_UNKNOWN_CL
+      );
+      equal(req1.status, Cr.NS_OK);
+      equal(req1.QueryInterface(Ci.nsIHttpChannel).responseStatus, 200);
       equal(buff, server.constructor.name);
       //Bug 1792187: Check if proxy is set to true when a proxy is used.
-      equal(req.QueryInterface(Ci.nsIHttpChannelInternal).isProxyUsed, true);
+      equal(req1.QueryInterface(Ci.nsIHttpChannelInternal).isProxyUsed, true);
       equal(
-        req.QueryInterface(Ci.nsIHttpChannel).protocolVersion,
+        req1.QueryInterface(Ci.nsIHttpChannel).protocolVersion,
         server.constructor.name == "NodeHTTP2Server" ? "h2" : "http/1.1"
       );
     }
@@ -222,22 +218,14 @@ add_task(async function test_https_proxy() {
       await server.execute(
         `global.server_name = "${server.constructor.name}";`
       );
-      await server.registerPathHandler("/test", (req, resp) => {
-        resp.writeHead(200);
-        resp.end(global.server_name);
-      });
-      let chan = makeChan(`${server.origin()}/test`);
-      let { req, buff } = await new Promise(resolve => {
-        chan.asyncOpen(
-          new ChannelListener(
-            (req, buff) => resolve({ req, buff }),
-            null,
-            CL_ALLOW_UNKNOWN_CL
-          )
-        );
-      });
-      equal(req.status, Cr.NS_OK);
-      equal(req.QueryInterface(Ci.nsIHttpChannel).responseStatus, 200);
+      await regiisterServerNamePathHandler(server, "/test");
+
+      let [req1, buff] = await channelOpenPromise(
+        makeChan(`${server.origin()}/test`),
+        CL_ALLOW_UNKNOWN_CL
+      );
+      equal(req1.status, Cr.NS_OK);
+      equal(req1.QueryInterface(Ci.nsIHttpChannel).responseStatus, 200);
       equal(buff, server.constructor.name);
     }
   );
@@ -271,22 +259,13 @@ add_task(async function test_http2_proxy() {
       await server.execute(
         `global.server_name = "${server.constructor.name}";`
       );
-      await server.registerPathHandler("/test", (req, resp) => {
-        resp.writeHead(200);
-        resp.end(global.server_name);
-      });
-      let chan = makeChan(`${server.origin()}/test`);
-      let { req, buff } = await new Promise(resolve => {
-        chan.asyncOpen(
-          new ChannelListener(
-            (req, buff) => resolve({ req, buff }),
-            null,
-            CL_ALLOW_UNKNOWN_CL
-          )
-        );
-      });
-      equal(req.status, Cr.NS_OK);
-      equal(req.QueryInterface(Ci.nsIHttpChannel).responseStatus, 200);
+      await regiisterServerNamePathHandler(server, "/test");
+      let [req1, buff] = await channelOpenPromise(
+        makeChan(`${server.origin()}/test`),
+        CL_ALLOW_UNKNOWN_CL
+      );
+      equal(req1.status, Cr.NS_OK);
+      equal(req1.QueryInterface(Ci.nsIHttpChannel).responseStatus, 200);
       equal(buff, server.constructor.name);
     }
   );
@@ -331,15 +310,7 @@ add_task(async function test_proxy_with_redirects() {
         });
 
         let chan = makeChan(`${server.origin()}/redirect`);
-        let { req, buff } = await new Promise(resolve => {
-          chan.asyncOpen(
-            new ChannelListener(
-              (req, buff) => resolve({ req, buff }),
-              null,
-              CL_ALLOW_UNKNOWN_CL
-            )
-          );
-        });
+        let [req, buff] = await channelOpenPromise(chan, CL_ALLOW_UNKNOWN_CL);
         equal(req.status, Cr.NS_OK);
         equal(req.QueryInterface(Ci.nsIHttpChannel).responseStatus, 200);
         equal(buff, server.constructor.name);
diff --git a/netwerk/test/unit/test_signature_extraction.js b/netwerk/test/unit/test_signature_extraction.js
index 7d621a45cc83..3d9db2bdbf23 100644
--- a/netwerk/test/unit/test_signature_extraction.js
+++ b/netwerk/test/unit/test_signature_extraction.js
@@ -52,12 +52,12 @@ function getTempFile(leafName) {
 function promiseSaverComplete(aSaver, aOnTargetChangeFn) {
   return new Promise((resolve, reject) => {
     aSaver.observer = {
-      onTargetChange: function BFSO_onSaveComplete(aSaver, aTarget) {
+      onTargetChange: function BFSO_onSaveComplete(saver, aTarget) {
         if (aOnTargetChangeFn) {
           aOnTargetChangeFn(aTarget);
         }
       },
-      onSaveComplete: function BFSO_onSaveComplete(aSaver, aStatus) {
+      onSaveComplete: function BFSO_onSaveComplete(saver, aStatus) {
         if (Components.isSuccessCode(aStatus)) {
           resolve();
         } else {
diff --git a/netwerk/test/unit/test_tls_server.js b/netwerk/test/unit/test_tls_server.js
index 43ec2e53658f..aff806af980d 100644
--- a/netwerk/test/unit/test_tls_server.js
+++ b/netwerk/test/unit/test_tls_server.js
@@ -91,8 +91,8 @@ function startServer(
 
       input.asyncWait(
         {
-          onInputStreamReady(input) {
-            NetUtil.asyncCopy(input, output);
+          onInputStreamReady(input1) {
+            NetUtil.asyncCopy(input1, output);
           },
         },
         0,
@@ -144,17 +144,17 @@ function startClient(port, sendClientCert, expectingAlert, tlsVersion) {
   let outputDeferred = PromiseUtils.defer();
 
   let handler = {
-    onTransportStatus(transport, status) {
+    onTransportStatus(transport1, status) {
       if (status === Ci.nsISocketTransport.STATUS_CONNECTED_TO) {
         output.asyncWait(handler, 0, 0, Services.tm.currentThread);
       }
     },
 
-    onInputStreamReady(input) {
+    onInputStreamReady(input1) {
       try {
-        let data = NetUtil.readInputStreamToString(input, input.available());
+        let data = NetUtil.readInputStreamToString(input1, input1.available());
         equal(data, "HELLO", "Echoed data received");
-        input.close();
+        input1.close();
         output.close();
         ok(!expectingAlert, "No cert alert expected");
         inputDeferred.resolve();
@@ -166,7 +166,7 @@ function startClient(port, sendClientCert, expectingAlert, tlsVersion) {
             errorCode == SSL_ERROR_BAD_CERT_ALERT
           ) {
             info("Got bad cert alert as expected for tls 1.2");
-            input.close();
+            input1.close();
             output.close();
             inputDeferred.resolve();
             return;
@@ -176,7 +176,7 @@ function startClient(port, sendClientCert, expectingAlert, tlsVersion) {
             errorCode == SSL_ERROR_RX_CERTIFICATE_REQUIRED_ALERT
           ) {
             info("Got cert required alert as expected for tls 1.3");
-            input.close();
+            input1.close();
             output.close();
             inputDeferred.resolve();
             return;
@@ -186,9 +186,9 @@ function startClient(port, sendClientCert, expectingAlert, tlsVersion) {
       }
     },
 
-    onOutputStreamReady(output) {
+    onOutputStreamReady(output1) {
       try {
-        output.write("HELLO", 5);
+        output1.write("HELLO", 5);
         info("Output to server written");
         outputDeferred.resolve();
         input = transport.openInputStream(0, 0, 0);
diff --git a/netwerk/test/unit/test_tls_server_multiple_clients.js b/netwerk/test/unit/test_tls_server_multiple_clients.js
index 3058ec10f03d..335fdd450b0a 100644
--- a/netwerk/test/unit/test_tls_server_multiple_clients.js
+++ b/netwerk/test/unit/test_tls_server_multiple_clients.js
@@ -42,8 +42,8 @@ function startServer(cert) {
 
       input.asyncWait(
         {
-          onInputStreamReady(input) {
-            NetUtil.asyncCopy(input, output);
+          onInputStreamReady(input1) {
+            NetUtil.asyncCopy(input1, output);
           },
         },
         0,
@@ -86,17 +86,17 @@ function startClient(port) {
   let outputDeferred = PromiseUtils.defer();
 
   let handler = {
-    onTransportStatus(transport, status) {
+    onTransportStatus(transport1, status) {
       if (status === Ci.nsISocketTransport.STATUS_CONNECTED_TO) {
         output.asyncWait(handler, 0, 0, Services.tm.currentThread);
       }
     },
 
-    onInputStreamReady(input) {
+    onInputStreamReady(input1) {
       try {
-        let data = NetUtil.readInputStreamToString(input, input.available());
+        let data = NetUtil.readInputStreamToString(input1, input1.available());
         equal(data, "HELLO", "Echoed data received");
-        input.close();
+        input1.close();
         output.close();
         inputDeferred.resolve();
       } catch (e) {
@@ -104,9 +104,9 @@ function startClient(port) {
       }
     },
 
-    onOutputStreamReady(output) {
+    onOutputStreamReady(output1) {
       try {
-        output.write("HELLO", 5);
+        output1.write("HELLO", 5);
         info("Output to server written");
         outputDeferred.resolve();
         input = transport.openInputStream(0, 0, 0);