diff --git a/td/telegram/AnimationsManager.cpp b/td/telegram/AnimationsManager.cpp
index a75b554c9..f00230b44 100644
--- a/td/telegram/AnimationsManager.cpp
+++ b/td/telegram/AnimationsManager.cpp
@@ -312,7 +312,7 @@ bool AnimationsManager::merge_animations(FileId new_id, FileId old_id, bool can_
     if (old_->thumbnail != new_->thumbnail) {
       //    LOG_STATUS(td_->file_manager_->merge(new_->thumbnail.file_id, old_->thumbnail.file_id));
     }
-    if (old_->mime_type == "image/gif" && new_->mime_type == "video/mp4") {
+    if (new_->file_name.size() == old_->file_name.size() + 4 && new_->file_name == old_->file_name + ".mp4") {
       need_merge = false;
     }
   }