When the new permission for send_messages_in_threads was added, we added
the wrong bit. Instead of adding the bit as the most significant (37),
we added it as the last significant, which invalidated most of the
permissions defined by this method.
Discord has renamed / repurposed "Use Public Threads" and "Use Private
Threads", as well as added a new permission "Send Messages in Threads".
For more information, see:
https://github.com/discord/discord-api-docs/pull/3672
Currently creating a new thread uses a default auto archive duration of
1440 minutes, or 1 day.
Rather than prescribing our own default, we can use the default auto
archive duration that is set on the channel. This ensures that newly
created threads will respect the default auto archive duration as
prescribed by the user.
James GayferandGitHub