EDIT: Apologies. Updated with a link to what gorhill REALLY said:
Manifest v2 uBO will not be automatically replaced by Manifest v3 uBOL[ight]. uBOL is too different from uBO for it to silently replace uBO – you will have to explicitly make a choice as to which extension should replace uBO according to your own prerogatives.
Ultimately whether uBOL is an acceptable alternative to uBO is up to you, it’s not a choice that will be made for you.
Will development of uBO continue? Yes, there are other browsers which are not deprecating Manifest v2, e.g. Firefox.
why not?
Why?
a good reason is that they are controlled by Google and without competition they can implement any anti-consumer features they want
No they’re not. You don’t know what you’re talking about.
None of the other Chromium based browsers have the engineering power to go their own way. They are dependent on what Google adds or removes in Chromium.
Wrong again.