Somewhat of a PSA for Qt users:
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. https://www.firefox.com/en-US/firefox/149.0/releasenotes/
Edit: I talk about a patched version below, but it was an about:config toggle in more recent times.
Always needed a patched version of Firefox before for that. Presumably most distros will transparently throw that patch out of their Firefox package, so likely don’t have to do anything.
But well, you don’t specifically need a patched version anymore for that, so if that’s a separate package on your distro, you could consider using the normal package again. Although, I believe there’s also still patches floating about for using the KDE mimetype system…
My version is KDE patched, the actual browser I use is Librewolf, but I keep the distro package of Googlyfox around for when I need to use a less securely configured browser that allows redirects and captive portals and doesn’t block bot checks that use cross site javascript and WebGL contenta and browswer fingerprinting and…