Thank you for your bug-report. so there might not be much you can do here I guess. Indeed; it's unlikely to be a problem with 4Pane itself, but rather coming from the wxWidgets toolkit. And I won't be able to reproduce the bug as I don't multi-monitor. Anyway, which distro/version are you using? And which wxWidgets version? (You can find the latter by doing Ctrl-Alt-Middleclick inside any wxWidgets app.) The latest wxWidgets release is 3.2.6. If you are using something much earlier, it would be worth...
Thanks again. In my senility I'd completely forgotten about wxFileName::CreateTempFileName. Now committed.
A better fix for https://sourceforge.net/p/fourpane/bugs/22/, thanks to Wolfgang Frisch
Thank you for your report, and I apologise for the delay. This is now fixed by #d8b74e. However I couldn't reproduce this here (debian) or in openSUSE 15.6. Though the behaviour you describe should in theory have occurred, in practice the file failed to be overwritten. Did it actually happen in tumbleweed?
When previewing an svg file, make the string name unguessable; see https://sourceforge.net/p/fourpane/bugs/22/
Fix viewing svg images broken by #1a65861
Replace the definition string '__WXGTK20__' with the more generic '__WXGTK__'
No real changes, just remove redundant code