neowin[.]net/news/microsoft-begins-turning-off-ublock-origin-and-other-extensions-in-edge/
windowscentral[.]com/software-apps/browsing/microsoft-edge-follows-in-google-chromes-footsteps-blocks-ublock-origin
windowscentral[.]com/software-apps/browsing/google-is-killing-ublock-origin-here-are-your-options
bleepingcomputer[.]com/news/security/firefox-continues-manifest-v2-support-as-chrome-disables-mv2-ad-blockers/
So far the block is only showing up in the Alpha [Canary] preview version of Edge, so you've got a little while yet if you use an extension that relies on Manifest V.2, e.g., uBlock. Firefox does continue to support Manifest V.2.