Implement a better file chooser / picker via xdg-desktop-portal-xapp

[billyswong]

Background:
https://www.firefox.com/en-US/firefox/149.0/releasenotes/

On Linux, Firefox will now default to the XDG portal file picker if available, rather than the GTK3 one, which is usually better integrated with the user's desktop environment, and more powerful.

The GTK3 file picker has been complained many many times by many people. Often we just conclude it is out of scope of What Linux Mint can do. But it might not be totally true.

More and more applications are shifting away from invoking the GTK file dialog directly. They send their request to XDG desktop portal and let it take care instead. This lead to an opportunity. Linux Mint may be able to intercept the request, and provide a better file picker dialog!

[mtwebster]

Not sure I agree with the release notes statement - it'll usually still be gtk-based, but gtk4 instead (which isn't really a good thing feature-wise).

This has been something I want to look at for some time - the obvious choice for us would be to have something that looks and feels like nemo, but it's not simple to do.

We could do a Gtk3 dialog with a much better-populated sidebar, which to me is the biggest problem with the default one.

[billyswong]

I guess they mean it for people who run KDE or COSMIC?

[AttilaLL]

I think the biggest problem is it's crappy picture/video preview/thumbnailing. It would be great to have big thumbnailed icons in it.
Also when you implement it would be great to keep support for network locations (connections from samba, ssh, etc..)