Many here have likely heard of Vanced. It was an ad-free version of Youtube (for Android) that removed ads and gave many advanced features. The only way to install was through either their Manager to install the apk's, or just installing apk's that they provided. I don't think they ever had a Github, so it was likely closed source. For whatever reason, it was discontinued in the last few months.
ReVanced aims to continue the legacy of Vanced. They have a Github page, and will not likely offer any modded Youtube apk's - instead opting to have users install their manager, which will then run a script to produce a modified Youtube apk on their devices. Both Vanced and ReVanced use their own version of MicroG if you want to sign in to your Youtube account.
I was wondering about the opinions of those here on whether or not this process that ReVanced employs is relatively safe, or is potentially a security/privacy hazard, even though the scripts are up on their Github page. For what it's worth, I am sure they will provide hashes so we can verify that the Manager app isn't compromised.
(I know that open-source doesn't equate to "safe". I would settle for "safer" than Vanced, as FOSS alternatives like NewPipe don't cut it for me at the moment.)