diff --git a/intl/components/src/Bidi.h b/intl/components/src/Bidi.h
index 7b901e6bfdf4..8db74173ed46 100644
--- a/intl/components/src/Bidi.h
+++ b/intl/components/src/Bidi.h
@@ -7,14 +7,10 @@
 #include "mozilla/intl/BidiEmbeddingLevel.h"
 #include "mozilla/intl/ICU4CGlue.h"
 
-// Restrict use of the Rust unicode-bidi implementation to Nightly builds,
-// pending investigation of perf regressions; Beta/Release builds will
-// continue to use the ICU4C implementation for now.
-#ifdef NIGHTLY_BUILD
-#  define USE_RUST_UNICODE_BIDI 1
-#else
-#  define USE_RUST_UNICODE_BIDI 0
-#endif
+// Use the Rust unicode-bidi crate to back the Bidi component.
+// (Define to 0 to use the legacy ICU4C implementation instead,
+// until that code is removed altogether.)
+#define USE_RUST_UNICODE_BIDI 1
 
 #if USE_RUST_UNICODE_BIDI
 #  include "mozilla/intl/unicode_bidi_ffi_generated.h"
diff --git a/layout/reftests/bidi/reftest.list b/layout/reftests/bidi/reftest.list
index c9e77cd88aa4..7a73ea356b1f 100644
--- a/layout/reftests/bidi/reftest.list
+++ b/layout/reftests/bidi/reftest.list
@@ -177,7 +177,7 @@ fuzzy-if(cocoaWidget,0-1,0-3) fuzzy-if(Android,0-1,0-6) == brackets-3a-rtl.html
 == 1231175-1.html 1231175-1-ref.html
 == 1366623-1.html 1366623-1-ref.html
 == 1426042-1.html 1426042-1-ref.html # Bug 1392106
-fails-if(release_or_beta) == clone-intrinsic-size-bidi.html clone-intrinsic-size-bidi-ref.html
+== clone-intrinsic-size-bidi.html clone-intrinsic-size-bidi-ref.html
 fuzzy-if(winWidget,70-112,8-8) == slice-intrinsic-size-bidi.html slice-intrinsic-size-bidi-ref.html
 == 1556414-1.html 1556414-1-ref.html
 == 1567036-1.html 1567036-1-ref.html
diff --git a/testing/web-platform/meta/css/CSS2/bidi-text/bidi-011.xht.ini b/testing/web-platform/meta/css/CSS2/bidi-text/bidi-011.xht.ini
index fdbb6405393f..ed6cff49cbc7 100644
--- a/testing/web-platform/meta/css/CSS2/bidi-text/bidi-011.xht.ini
+++ b/testing/web-platform/meta/css/CSS2/bidi-text/bidi-011.xht.ini
@@ -1,4 +1,2 @@
 [bidi-011.xht]
-  expected:
-    if nightly_build: FAIL
-    PASS
+  expected: FAIL
diff --git a/testing/web-platform/meta/css/CSS2/selectors/first-letter-punctuation-126.xht.ini b/testing/web-platform/meta/css/CSS2/selectors/first-letter-punctuation-126.xht.ini
index 037f1b123f35..160e042b6847 100644
--- a/testing/web-platform/meta/css/CSS2/selectors/first-letter-punctuation-126.xht.ini
+++ b/testing/web-platform/meta/css/CSS2/selectors/first-letter-punctuation-126.xht.ini
@@ -1,4 +1,2 @@
 [first-letter-punctuation-126.xht]
-  expected:
-    if nightly_build: FAIL
-    PASS
+  expected: FAIL
diff --git a/testing/web-platform/meta/css/CSS2/selectors/first-letter-punctuation-127.xht.ini b/testing/web-platform/meta/css/CSS2/selectors/first-letter-punctuation-127.xht.ini
index e338668afd65..91d07df4a10d 100644
--- a/testing/web-platform/meta/css/CSS2/selectors/first-letter-punctuation-127.xht.ini
+++ b/testing/web-platform/meta/css/CSS2/selectors/first-letter-punctuation-127.xht.ini
@@ -1,4 +1,2 @@
 [first-letter-punctuation-127.xht]
-  expected:
-    if nightly_build: FAIL
-    PASS
+  expected: FAIL
diff --git a/testing/web-platform/meta/css/CSS2/text/white-space-collapsing-bidi-001.xht.ini b/testing/web-platform/meta/css/CSS2/text/white-space-collapsing-bidi-001.xht.ini
deleted file mode 100644
index db11e0c36e3e..000000000000
--- a/testing/web-platform/meta/css/CSS2/text/white-space-collapsing-bidi-001.xht.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[white-space-collapsing-bidi-001.xht]
-  expected:
-    if nightly_build: PASS
-    FAIL
diff --git a/testing/web-platform/meta/css/css-text/white-space/white-space-collapse-002.html.ini b/testing/web-platform/meta/css/css-text/white-space/white-space-collapse-002.html.ini
index d9e7e86adde1..7ac4a17bce86 100644
--- a/testing/web-platform/meta/css/css-text/white-space/white-space-collapse-002.html.ini
+++ b/testing/web-platform/meta/css/css-text/white-space/white-space-collapse-002.html.ini
@@ -1,44 +1,4 @@
 [white-space-collapse-002.html]
-  [RLO 2]
-    expected:
-      if nightly_build: PASS
-      FAIL
-
-  [RLO 3]
-    expected:
-      if nightly_build: PASS
-      FAIL
-
-  [RLO 4]
-    expected:
-      if nightly_build: PASS
-      FAIL
-
-  [RLO 5]
-    expected:
-      if nightly_build: PASS
-      FAIL
-
-  [RLE 2]
-    expected:
-      if nightly_build: PASS
-      FAIL
-
-  [RLE 3]
-    expected:
-      if nightly_build: PASS
-      FAIL
-
-  [RLE 4]
-    expected:
-      if nightly_build: PASS
-      FAIL
-
-  [RLE 5]
-    expected:
-      if nightly_build: PASS
-      FAIL
-
   [RLM 2]
     expected: FAIL