D’oh. It’s back.
Running 1.26.77 now, although I don’t know if the issue aligns exactly with the update to this version. I believe it was working fine for a short while even after the update but not 100% sure.
But, whatever the issue is, this one has come back at the same time: Desktop freezes when right click a bookmark both in bookmark bar and manager - #4 by JimB1
So I do think they are related.