Fix previous commit (ref #219) and update catch_up config comment

example-config.yaml

@@ -133,7 +133,7 @@ bridge:
     # Remember that proper sticker support always requires Pillow to convert webp into png.
     native_stickers: true
     # Whether or not to fetch and handle Telegram updates at startup from the time the bridge was down.
-    # WARNING: Probably buggy, might get stuck in infinite loop.
+    # Currently only works for private chats and normal groups.
     catch_up: false
     # Whether or not to use /sync to get presence, read receipts and typing notifications when using
     # your own Matrix account as the Matrix puppet for your Telegram account.

mautrix_telegram/abstract_user.py

@@ -353,7 +353,7 @@ class AbstractUser(ABC):
     async def update_message(self, original_update: UpdateMessage) -> None:
         update, sender, portal = self.get_message_details(original_update)
 
-        if self.bot and not portal.mxid:
+        if self.is_bot and not portal.mxid:
             self.log.debug(f"Ignoring message received by bot in unbridged chat %s",
                            portal.tgid_log)
             return