Well now I am officially going nuts. I used Frescobaldi for years until it recently slowed down to unacceptably ling editor response times (tens of seconds to position the cursor, in only 20 pages of code). This was discussed on the list. Not yet resolved. Needs work.
So I happily moved over to emacs and point and click, having been an emacs user (but not an emacs hacker) for decades. The indentation mode is a complete failure. This has been discussed on the list for years. But that's OK. It's other strengths outweigh that. Now, at 60 pages of string quartet score, lilypond-mode has also slowed down to molasses-like flow rates. It too has become unusable. [I am somewhat gobsmacked by this.]
So I decided to go over to vim. I have used vi for decades, but the Lilypond doco refers to gvim so I am trying that. Gvim is new to me. I followed everything the Lilypond manual says, unset everything to do with emacs, as far as I can tell, and no matter what I do. after several reboots and all, clicking on a newly generated PDF brings up emacs, not a buffer in gvim.
I recreated the GNOME 3 desktop auxiliary file just in case. No better.
Does anybody have a clue as to what is happening here? As far as I can see the links in the PDF point to the generic 'textedit', not emacs.
Andrew