1 files changed, 25 insertions, 0 deletions
diff --git a/src/SMAPI/Framework/ContentManagers/GameContentManager.cs b/src/SMAPI/Framework/ContentManagers/GameContentManager.cs
index f8ee575f..e3d1e569 100644
--- a/src/SMAPI/Framework/ContentManagers/GameContentManager.cs
+++ b/src/SMAPI/Framework/ContentManagers/GameContentManager.cs
@@ -140,6 +140,31 @@ namespace StardewModdingAPI.Framework.ContentManagers
                 this.Monitor.Log($"Invalidated {invalidated.Length} asset names: {string.Join(", ", invalidated)} for locale change.", LogLevel.Trace);
         }
 
+        /// <inheritdoc />
+        public override void OnReturningToTitleScreen()
+        {
+            // The game clears LocalizedContentManager.localizedAssetNames after returning to the title screen. That
+            // causes an inconsistency in the SMAPI asset cache, which leads to an edge case where assets already
+            // provided by mods via IAssetLoader when playing in non-English are ignored.
+            //
+            // For example, let's say a mod provides the 'Data\mail' asset through IAssetLoader when playing in
+            // Portuguese. Here's the normal load process after it's loaded:
+            //   1. The game requests Data\mail.
+            //   2. SMAPI sees that it's already cached, and calls LoadRaw to bypass asset interception.
+            //   3. LoadRaw sees that there's a localized key mapping, and gets the mapped key.
+            //   4. In this case "Data\mail" is mapped to "Data\mail" since it was loaded by a mod, so it loads that
+            //      asset.
+            //
+            // When the game clears localizedAssetNames, that process goes wrong in step 4:
+            //  3. LoadRaw sees that there's no localized key mapping *and* the locale is non-English, so it attempts
+            //     to load from the localized key format.
+            //  4. In this case that's 'Data\mail.pt-BR', so it successfully loads that asset.
+            //  5. Since we've bypassed asset interception at this point, it's loaded directly from the base content
+            //     manager without mod changes.
+            if (LocalizedContentManager.CurrentLanguageCode != LocalizedContentManager.LanguageCode.en)
+                this.InvalidateCache((_, _) => true);
+        }
+
         /// <summary>Create a new content manager for temporary use.</summary>
         public override LocalizedContentManager CreateTemporary()
         {