The Test Case I included in the description is being fixed in Ubuntu 24.10 by having nautilus provide the filechooser used by xdg desktop portals (which is what the Chromium and Firefox snaps use for the filechooser).
The Test Case I included in the description is being fixed in Ubuntu 24.10 by having nautilus provide the filechooser used by xdg desktop portals (which is what the Chromium and Firefox snaps use for the filechooser).