System editor save and load dialogs not showing on Windows

[nozmajner]

Observed behaviour

Open or save as dialogs aren't appearing on Windows.
After opening or saving a system, neither the Save as or Open dialogs work. Neither with the menu entry or the hotkeys.
The "please wait" dialog opens for a second then disappears, and nothing happens. Plain Save and ctrl+S still works.

Expected behaviour

Save and load dialogs to be shown.

Steps to reproduce

Save a custom system. After saving, try to Save as... or Open another system.

syseditor-issue.mp4

win10, 2024-0203 release, and consequent builds.

Broken out from #5746 for future tracking.

@nozmajner could you break the missing editor open/save dialogs on Windows into a separate issue report? I'm not seeing anything obvious that would resolve that issue from the upstream dependency (https://github.com/samhocevar/portable-file-dialogs) but maybe @fluffyfreak could take a look at it and check it under a debugger?