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.
Worth keeping around at least
Out of principle, I refuse to pretend I am not browsing with Firefox. 🦊❤️✊ Let website statistics show! And I will boycott sites that break due to not testing on multiple browsers!
That works until it’s your bank or credit card website. I cannot use Capital One’s (CC) “pay bill” any longer.
Change banks
Luckily it hasn’t come to that for me yet. But I have reported issues with my bank’s website to them, and it had been fixed.