diff --git a/css/selectors/after.json b/css/selectors/after.json
index a30add8146680b..ef8e58919d1755 100644
--- a/css/selectors/after.json
+++ b/css/selectors/after.json
@@ -138,7 +138,7 @@
               "chrome_android": "mirror",
               "edge": "mirror",
               "firefox": {
-                "version_added": false
+                "version_added": "143"
               },
               "firefox_android": "mirror",
               "oculus": "mirror",
@@ -153,7 +153,7 @@
               "webview_ios": "mirror"
             },
             "status": {
-              "experimental": true,
+              "experimental": false,
               "standard_track": true,
               "deprecated": false
             }
diff --git a/css/selectors/before.json b/css/selectors/before.json
index 65aad7cea69de7..2a92b72cc507e6 100644
--- a/css/selectors/before.json
+++ b/css/selectors/before.json
@@ -155,7 +155,7 @@
               "chrome_android": "mirror",
               "edge": "mirror",
               "firefox": {
-                "version_added": false
+                "version_added": "143"
               },
               "firefox_android": "mirror",
               "oculus": "mirror",
@@ -170,7 +170,7 @@
               "webview_ios": "mirror"
             },
             "status": {
-              "experimental": true,
+              "experimental": false,
               "standard_track": true,
               "deprecated": false
             }