uBO is a Manifest v2 extension, hence the warning in your Google Chrome browser. There is no Manifest v3 version of uBO, hence the browser will suggest alternative extensions as a replacement for uBO:
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uBO Lite (uBOL) is a pared-down version of uBO with a best effort at converting filter lists used by uBO into a Manifest v3-compliant approach, with a focus on reliability and efficiency as has been the case with uBO since first published in June 2014.
However the focus on reliability and efficiency in a Manifest v3 environment meant having to sacrifice many features beyond those not possible within a Manifest v3 framework.
I recommend using Adguard Mv3… Its the best I’ve found.
Unfortunately, uBlock Origin Lite seems to not want to implement the basic feature of adding your own rules even though Mv3 would allow it, albeit in limited quantities.
It sucks, because they are the best at dealing with YouTube’s adblock. Adguard occasionally messes that up.
That said, with a bit of messing with policy settings, you can keep uBlock Origin until 2025. Or you can consider switching to a browser like Brave with a built in adblock, or check out Supermium which is attempting to keep Mv2 support. Or, yes, move to Firefox where uBlock Origin still works, even under Mv3. (They kept features a Google removed.)
While Google turns off support for home users immediately, it is giving Enterprise customers an option to extend support by one year. Good news is that you can also utilize this to extend support.