Firefox 151 ships CSS @container range syntax (#29804)

Author: Elchi3

css/at-rules/container.json

@@ -396,23 +396,7 @@
                 "chrome_android": "mirror",
                 "edge": "mirror",
                 "firefox": {
-                  "version_added": "preview",
-                  "flags": [
-                    {
-                      "type": "preference",
-                      "name": "layout.css.style-queries.enabled",
-                      "value_to_set": "true"
-                    },
-                    {
-                      "type": "preference",
-                      "name": "layout.css.attr.enabled",
-                      "value_to_set": "true"
-                    }
-                  ],
-                  "impl_url": [
-                    "https://bugzil.la/1986631",
-                    "https://bugzil.la/1998245"
-                  ]
+                  "version_added": "151"
                 },
                 "firefox_android": "mirror",
                 "oculus": "mirror",
@@ -427,7 +411,7 @@
                 "webview_ios": "mirror"
               },
               "status": {
-                "experimental": true,
+                "experimental": false,
                 "standard_track": true,
                 "deprecated": false
               }