It's the last few months of support for uBlock Origin in Chrome.

• uBlock Origin Lite is an alternative.
• adGuard is an alternative
• Firefox with uBlock Origin is an alternative

See the Chrome Web Store migration plan.

The following file should extend support in Chrome until June 2025. (See link above for Chromium or Edge.) Put it here with these permissions and owner:

$ ls -l /etc/opt/chrome/policies/managed/ExtensionManifestV2Availability.json
-rw-r--r-- 1 root root 43 Dec 27 23:36 ExtensionManifestV2Availability.json

ExtensionManifestV2Availability.json

{
  "ExtensionManifestV2Availability": 2
}