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E-os Google 2fa?
(lemm.ee)
For 2FA app you can try Aegis authentificator it is FOSS. Instead of using Google's 2FA.
The yes/no popup requires play services to function so likely your answer is no. As for youtube try out newpipe
F-Droid is an installable catalogue of FOSS (Free and Open Source Software) applications for the Android platform. The client makes it easy to browse, install, and keep track of updates on your device.
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