From second paragraph “I wonder if I started noticing the problem under Ubuntu 14.x, but I'm pretty sure it was there already at Ubuntu 16.x. I'm now running Ubuntu 19.10 and Gnome 3.34.2. (Just for the record, the bug also persisted in Ubu 18.04 for as long as I was using it.)”
The bug was infact the reason I updated to 19.04 and later to 19.10, but it did not go away.
From second paragraph “I wonder if I started noticing the problem under Ubuntu 14.x, but I'm pretty sure it was there already at Ubuntu 16.x. I'm now running Ubuntu 19.10 and Gnome 3.34.2. (Just for the record, the bug also persisted in Ubu 18.04 for as long as I was using it.)”
The bug was infact the reason I updated to 19.04 and later to 19.10, but it did not go away.