Hello,
Documentation`HelpLookupPacletURI
is broken on Linux in 11.1. It opens a notebook window that has no search bar or navigation buttons. I thought it would get fixed for 11.1.1, but it wasn't.
So now I am asking here: Is there a workaround for this issue?
To test, try e.g.
Documentation`HelpLookupPacletURI["ref/FindRoot"]