Bug 1829907 - Pocket newtab fixing locale list region issue in nightly. r=gvn

Differential Revision: https://phabricator.services.mozilla.com/D176449

UltraBlame original commit: 9d6128141763194af587c1c5a19bc320ad088a97

Author: marco-c

browser/components/newtab/lib/DiscoveryStreamFeed.jsm

@@ -145,12 +145,19 @@ class DiscoveryStreamFeed {
     if (this._isBff === undefined) {
       const pocketConfig =
         this.store.getState().Prefs.values?.pocketConfig || {};
+
+      const preffedLocaleListString = pocketConfig.localeListConfig || "";
+      const preffedLocales = preffedLocaleListString
+        .split(",")
+        .map(s => s.trim());
+      const localeEnabled = this.locale && preffedLocales.includes(this.locale);
+
       const preffedRegionBffConfigString = pocketConfig.regionBffConfig || "";
       const preffedRegionBffConfig = preffedRegionBffConfigString
         .split(",")
         .map(s => s.trim());
       const regionBff = preffedRegionBffConfig.includes(this.region);
-      this._isBff = regionBff;
+      this._isBff = !localeEnabled && regionBff;
     }
 
     return this._isBff;