Lately, even Empathy in Fedora 23 could not start Facebook chat (2015 Dec). Empathy asked for password every time it wanted to login; although you already had entered the password correctly, Empathy rejected it.
How about Pidgin?
What you need is libfacebook.so (could be downloaded here). Copy it into “/usr/lib64/purple-2” (need root mode). If you already have Pidgin run, restart it.
(Additional note) Debian-based user should place the corresponding file into “/usr/lib/purple-2” instead of lib64.
In-sha-Allah this would enable Facebook support for Pidgin.
Original source: https://github.com/jgeboski/purple-facebook/wiki