diff --git a/js/src/tests/user.js b/js/src/tests/user.js
index 8bde3d9865f2..7ff17540c26e 100644
--- a/js/src/tests/user.js
+++ b/js/src/tests/user.js
@@ -32,6 +32,5 @@ user_pref("browser.webapps.checkForUpdates", 0);
 user_pref("javascript.options.weakrefs", true);
 user_pref("javascript.options.experimental.weakrefs.expose_cleanupSome", true);
 user_pref("javascript.options.experimental.iterator_helpers", true);
-user_pref("javascript.options.experimental.private_fields", true);
 user_pref("javascript.options.experimental.top_level_await", true);
 user_pref("javascript.options.experimental.ergonomic_brand_checks", true);
diff --git a/js/xpconnect/tests/chrome/chrome.ini b/js/xpconnect/tests/chrome/chrome.ini
index 19e864ffc1f7..bce11f0f612e 100644
--- a/js/xpconnect/tests/chrome/chrome.ini
+++ b/js/xpconnect/tests/chrome/chrome.ini
@@ -32,7 +32,6 @@ support-files =
   !/js/xpconnect/tests/mochitest/file_evalInSandbox.html
   !/js/xpconnect/tests/mochitest/file_xrayic.html
 prefs =
-  javascript.options.experimental.private_fields=true
   javascript.options.large_arraybuffers=true
   javascript.options.experimental.ergonomic_brand_checks=true
   
diff --git a/js/xpconnect/tests/mochitest/mochitest.ini b/js/xpconnect/tests/mochitest/mochitest.ini
index 0de7ebdc94aa..5ec2ce70fea4 100644
--- a/js/xpconnect/tests/mochitest/mochitest.ini
+++ b/js/xpconnect/tests/mochitest/mochitest.ini
@@ -41,7 +41,6 @@ support-files =
   bug1681664_helper.js
 prefs =
   javascript.options.weakrefs=true
-  javascript.options.experimental.private_fields=true
   javascript.options.experimental.ergonomic_brand_checks=true
   javascript.options.experimental.top_level_await=true
 
diff --git a/modules/libpref/init/StaticPrefList.yaml b/modules/libpref/init/StaticPrefList.yaml
index 085c9ea41d24..ecb7bca1cfba 100644
--- a/modules/libpref/init/StaticPrefList.yaml
+++ b/modules/libpref/init/StaticPrefList.yaml
@@ -5661,12 +5661,6 @@
     value: false
     mirror: always
 
-  # Experimental support for Private Fields in JavaScript.
--   name: javascript.options.experimental.private_fields
-    type: bool
-    value: false
-    mirror: always
-
   # Experimental support for Private Methods in JavaScript.
 -   name: javascript.options.experimental.private_methods
     type: bool
@@ -5674,6 +5668,12 @@
     mirror: always
 #endif  // NIGHTLY_BUILD
 
+  # Support for Private Fields in JavaScript.
+- name: javascript.options.experimental.private_fields
+  type: bool
+  value: true
+  mirror: always
+
   # Experimental support for the ergonomic brand check proposal.
 - name: javascript.options.experimental.ergonomic_brand_checks
   type: bool
diff --git a/toolkit/components/extensions/test/xpcshell/xpcshell-content.ini b/toolkit/components/extensions/test/xpcshell/xpcshell-content.ini
index 0950f7a9d3c2..e7a0b5f262ae 100644
--- a/toolkit/components/extensions/test/xpcshell/xpcshell-content.ini
+++ b/toolkit/components/extensions/test/xpcshell/xpcshell-content.ini
@@ -1,7 +1,3 @@
-[DEFAULT]
-prefs =
-  javascript.options.experimental.private_fields=true
-
 [test_ext_i18n.js]
 skip-if = os == "android" || (os == "win" && debug) || (os == "linux")
 [test_ext_i18n_css.js]