> Don't know where you got the info about 8.0 being the last to support mv2

I updated to whatever the next version was, and it disabled all my MV2 extensions (mainly uBO). I figured that they kept MV2 support going as long as they could, and there was recently a patch by Google that removed the support for good, so that must be the end of it. So I downgraded back.

Did you have to do anything to reenable MV2 extensions? Or maybe it was a just bug they fixed later?

This was true, temporarily with some snapshot builds, for whatever reason. At some point MV2 extensions started to work again. That said, I imagine there will be a point where keeping MV2 working would be untenable. I seem to remember reading something that indicated that that was why they were beefing up the internal ad-blocker.