I finally found 4 related fonts (ttf) which caused every Lister to abort (fade away without saying anything). This was in a directory of ~3k fonts and I could see and access the other fonts until (?Dopus) read the subject file and aborted.
During the Open time there is 100% cpu usage which could last 15 seconds or so. As I cut the number of files down the time got shorter and shorter until I didn't see the Lister at all.
In Font Creator (font editor) I could see nothing very peculiar about them but I removed their hinting and that solved the problem with the Listers.
Is there something that Dopus is/shouldn't be doing on these fonts? They are accepted by all my other font programs. Before-After.zip (324 KB)
FYI - I have another error "working" -- in a group of 250 fonts, so it's not just the previous 4 which have a problem. I'm not looking for them, they just show up. They're hard to isolate so I don't know how many or anything.
I've been working large numbers of fonts for years with Dopus and has never happened before.
Hurray. Vn 9.1.1.3 is working just fine on all my problem fonts. Whatever "adjustment" you made addressed it all. Thank you for looking into this right away and for issuing an immediate fix.
(Sorry I already bought Vn 9 so can't send anymore money!)