Note for others unable to login about fbchat

[kattstof]

For reference i'm using python 3.7 and it's working flawlessly for me. sadly i'm not sure what in 3.9 caused fbchat compatibility to break, i'll see if i can figure WHAT caused it to break and then put in a pull request

[dotSIS]

works for me too, but once the account is logged out the login issue happens.
I have python 3.8.2 and revision = 1 and currently cant login.

[raidgar98]

works for me
I've printed r.text, and I can't find 'client_revision' in HTML result, so this is a problem

[kennethbruskiewicz]

Running the client in debug mode in Python 3.9.7, and using this revision workaround, seems to work for logging in successfully for me. Note I am using a downgraded user-agent as recommended here: #657 (comment)