For a while now the transition away from Manifest V2 (MV2) to MV3 has been on-going and it looks like it is entering its final phase of deprecation, at least, in the case of Google Chrome. A recent discussion thread in the w3c WebExtensions Community Group GitHub repo has highlighted how the latest and upcoming versions of the most popular browser are expected to be its final releases with support for MV2 extensions.
What this essentially means is that the tricks and bypasses that were used to keep MV2 extensions like uBlock Origin and others alive will not work any more on Chrome, or at least not for very long. For example the Windows Registry mod that could extend MV2 availability will cease to function after Chromium version 151.
I think there's one called user agent switcher.
Websites that magically work when you change UA.
Oh, not off the top of my head. I can recall at least twice when it worked for me but I can't remember what sites I was visiting. My sister tried to access ticketmaster I think which was blocking her for some reason (She doesn't use a VPN) so I told her to try a user agent switcher. It worked after switching her user agent to Chrome. I'm not saying they delibritly block Firefox but it worked in this instance.