VS code is technically not open-source since it has many proprietary blobs on top. VScodium is the fully open-source version.
I don't know how much can Revanced be considered open-source except for their Revanced manager app since you still use the patched versions of the proprietary Google apps.
Sorry for being pedantic.
With the latest 47 release I think the fractional scaling got to the point where it's a perfectly usable in almost all cases. I use it on 125% and don't see any blurred apps or glitches or anything like that.