diff --git a/toolkit/components/extensions/test/browser/browser_ext_themes_experiment.js b/toolkit/components/extensions/test/browser/browser_ext_themes_experiment.js
index 50f8cf9f8f4a..8e56a8c0fec5 100644
--- a/toolkit/components/extensions/test/browser/browser_ext_themes_experiment.js
+++ b/toolkit/components/extensions/test/browser/browser_ext_themes_experiment.js
@@ -3,9 +3,11 @@
 // This test checks whether the theme experiments work
 
 add_task(async function setup() {
-  await SpecialPowers.pushPrefEnv({
-    set: [["extensions.legacy.enabled", true]],
-  });
+  if (AppConstants.MOZ_ALLOW_LEGACY_EXTENSIONS) {
+    await SpecialPowers.pushPrefEnv({
+      set: [["extensions.legacy.enabled", true]],
+    });
+  }
 });
 
 add_task(async function test_experiment_static_theme() {
diff --git a/toolkit/components/extensions/test/browser/browser_ext_themes_warnings.js b/toolkit/components/extensions/test/browser/browser_ext_themes_warnings.js
index f43b2beffef7..1956a7d8a13e 100644
--- a/toolkit/components/extensions/test/browser/browser_ext_themes_warnings.js
+++ b/toolkit/components/extensions/test/browser/browser_ext_themes_warnings.js
@@ -73,7 +73,9 @@ add_task(async function test_dynamic_theme() {
 });
 
 add_task(async function test_experiment() {
-  Services.prefs.setBoolPref("extensions.legacy.enabled", true);
+  await SpecialPowers.pushPrefEnv({
+    set: [["extensions.legacy.enabled", true]],
+  });
 
   info("Testing that experiments are handled correctly when legacy pref is enabled");
 
@@ -107,7 +109,7 @@ add_task(async function test_experiment() {
 
   info("Testing that experiments are handled correctly when legacy pref is disabled");
 
-  Services.prefs.setBoolPref("extensions.legacy.enabled", false);
+  await SpecialPowers.popPrefEnv();
 
   extension = ExtensionTestUtils.loadExtension({
     manifest: {
diff --git a/toolkit/mozapps/extensions/content/aboutaddons.css b/toolkit/mozapps/extensions/content/aboutaddons.css
index ad6b4fec73e6..b661716fd8cf 100644
--- a/toolkit/mozapps/extensions/content/aboutaddons.css
+++ b/toolkit/mozapps/extensions/content/aboutaddons.css
@@ -68,7 +68,6 @@ addon-list .addon.card {
 .addon-name {
   font-size: 16px;
   font-weight: 600;
-  color: var(--grey-90);
   line-height: 22px;
   /* Subtract the top line-height so the text and icon align at the top. */
   margin-top: -3px;
@@ -194,6 +193,8 @@ button[action="more-options"] {
   width: 24px;
   height: 24px;
   margin: 0;
+  -moz-context-properties: fill;
+  fill: currentColor;
   background: url("chrome://global/skin/icons/more.svg") no-repeat center center;
 }