@smcv As it happens, I was researching the bug, the various sites I visited seemed to point to glib2 as being the source, and as I have debian testing/sid, I naturally looked up glib bugs in debian, and found this bug report.
Since I had found more about the resolution of the bug from the pkg source in GitLab than was reported here, I thought I'd report what I'd found, so people would know about it. I personally use debian LXQt , but up until now had (as I had with Lubuntu LXDE/LXQt before) had attempted to use the standard user-dirs.dirs to try to redirect programs' attempts to use the /home/<user>/Documents (etc.) directories to my separate /data partition. Experience has shown that, except for my Desktop directory (by file managers), all other re-directed directories are totally ignored. In a bug-report discussion with Alf Gaida, he suggested I bind-mount my /data user directories to my /home/<user>/ directories, as being better than symlinking them (or using the user-dirs.dirs file). [He also said something called "User Mounts" would be even better, but I have yet to find out what he meant...] Since I had an old computer that I was setting up for use, in order to give it away, I decided to test bind mounts on it, before doing it for my debian install. I had just installed Peppermint 10, and tweaked it a bit, and then added the bind mount lines to /etc/fstab. It works, but adds all 8 mounts to the file manager as removable drives (and may also add to the desktop - not sure). Subsequent research suggested I could solve that by adding x-gvfs-hide to the fstab line, but this proved wrong. (See: https://bugs.launchpad.net/peppermint/+bug/1831302) Checking the GLib2 version in Peppermint 10, with the version on my debian testing/sid, and the one listed in GitLab as having fixed the problem, it seemed clear that if I did modify my debian's fstab in like manner, I would likely have the same problem as in Peppermint. I will probably try the bind mounts here on debian, and then also try the "fixed" version in experimental. I will report back what I find.