Since #Chrome has dropped manifest v3 (which apparently also breaks umatrix so there goes plan B), I've given #Falkon a try as my "this web site is broken in Firefox" browser, and I've been pleasantly surprised by the results. I checked, and yes, it is Chromium under the hood, and has no extensions (Bitwarden pls) but it's a really solid browser with solid built-in adblocking.
Side note: it IS a sad state of affairs that I a second browser installed basically day one of setting up a new OS because #Firefox can no longer reliably render web pages.