Okay, so I am tempted to start a new thread, due to this late breaking news.
All those problematic browsers start up in XFCE just fine, but not in TDE. I
was able to use vivaldi-snapshot to check my bank account. (I am pleased to
find out that I still have some money, and even a few beans more due to
interest. The library has not revoked my privileges for overdue books. And
oh, I have some packages to pick up at the post office. Just thought you'd
like to know what I have been missing without my usual browsers.) In any
case, if these work in XFCE, one would hope the same for TDE.
I am trying to trace any issues back to their sources, but from what I see by
comparing both desktops, it does seem to be caused by something Gnomish.
At this point, I think it can be declared to be a TDE problem (at least from
my perspective), and soon to be a problem for everybody who uses TDE; or
maybe just TDE with a Debian-based system, or maybe just TDE with Devuan. I
haven't sorted that part out yet.
It doesn't seem to have anything to do with non-free and contrib in my sources
list. At least, when I did an upgrade, it only upgraded packages that I
already had, and which I had recently upgraded without enabling non-free and
contrib in my sources.list.
I did already purge those gtk3 and gtk2 Trinity packages, as recommended by
Slavek, Nik, and others; doesn't seem to matter.
My guess is that this is an issue that others will also start to experience,
whenever next they do an upgrade or reinstallation. I don't know if it
affects Trinity's PSB or PTB repositories; so far I can't get out of the
stable builds.
I am off to hunt down any fugitive Gnomes hiding in my system If anybody has
any ideas or suggestions about these matters, I'd love to hear them.
Bill