Probably different themes are also a factor?
Maybe, I don't know for sure. I never messed around with themes to see if it made any difference.
I'm using Lubuntu (LXQT) right now. The Gtk 2/3 theme is set to `Arc-Dark`. But I've gotten those Gtk error/warning messages on almost every system I've used for multiple different apps, including systems using window managers built with Gtk.
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