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I gave it four stars because I just installed it,
and I haven't yet been able to test it thoroughly.

It doesn't work on Android!

Works. But if you wanna know how it works use Stylus extension and go to https(:)//uso(dot)kkx(dot)one/browse/styles and search for user-select blocker

Installed in Android 14 and FF 134.0.2. Enabled by default after installing. No change in being able to select text in Facebook.

Funktioniert nicht.

FF on Android. Allows text selection on comments on YouTube dot com without any hassle. thanks.