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Dark theme for messenger.com
< Feedback on Dark Theme for FB's Messenger
Tampermonkey 4.11.6120 (5 November 2020), Mozilla Firefox 86.0 (64-bit) - after applying the script and refreshing the https://www.messenger.com page, no changes were noticed.
I checked it and it works. Make sure you are logged into messenger, on the login page it doesn't work.
Tampermonkey 4.11.6120 (5 November 2020), Mozilla Firefox 86.0 (64-bit) - after applying the script and refreshing the https://www.messenger.com page, no changes were noticed.