PostWe've just released v13.9.

We've just released v13.9. Thank you to everyone who contributed to this release. As usual, upgrade using pip install -U python-telegram-bot. This release brings support for Bot API 5.5. ⚠️ There are a few things to mention about the API update. Since API 5.5 is online, • it is impossible to forward messages from some chats. Use the attributes Message/Chat.has_protected_content to check this. • users are able to send messages on behalf of channels they own. Bots are expected to use the attribute Message.sender_chat to correctly support such messages. • Bots are allowed to contact users who sent a join request to a chat where the bot is an administrator with the ChatMemberAdministrator.can_invite_users administrator right – even if the user never interacted with the bot before. • users can be mentioned by their ID in inline keyboards. This will only work in Telegram versions released after December 7, 2021. Older clients will display unsupported message. For the full list of changes and improvements, please see below. Please note that we are currently working towards v14 and will only make another 13.x.y release if there are serious bugs to be fixed or API updates to implement. As stated in our announcement from January, we don't know how long development for v14 will take. We expect v14 to be ready sometime in 2022. Major Changes: • Full Support for API 5.5 (#2809) Minor Changes: • Adjust Automated Locking of Inactive Issues (#2775)