On Chrome Version 114.0.5735.198 (Official Build) (64-bit), I don't see how to use the extension at all. There is no GIF/video/screenshots of usage on the extension page either now I cannot even say what button is missing.
I opened chrome://extensions/shortcuts but the extension doesn't even appear there.
A screenshot as on the other Clean Copy extension would help. But I suppose it just doesn't work on latest versions because it is 10 years old.
It is surprising that Chrome doesn't indicate the extension as incompatible with my version. I suppose there is just an automatic check that the API is correct, not a human who actually verifies that it behaves as it should.