[tomek@vz]

As uBlock Origin lead developer and maintainer Raymond Hill explained on Friday, this is the result of Google deprecating support for the Manifest v2 (MV2) extensions platform in favor of Manifest v3 (MV3).
“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,” Hill explained.
↫ Sergiu Gatlan at Bleeping Computer