This was going to be a question about Firefox being unable to display the file picker dialog, but I managed to find a solution that worked for me along the way. Since it was nowhere near the top of Google's results, I thought I'll share my solution in the hopes that this would help someone facing this same issue. The hardware: * Asus UM425IA Zenbook (AMD Ryzen 7 4700U CPU) Worked in: * Ubuntu 20.04 LTS * Firefox provided by APT repository * Xorg display server Not working in: * Ubuntu 22.04 LTS * Firefox 99.0.1 provided by snap * Wayland display server * File picker worked briefly on fresh install, but something (not sure what) quickly breaks file picker functionality The symptoms: * Firefox stopped being able to open file picker dialogs * Right clicking an image and selecting "Save Image As..." does nothing * With forms that accept file upload (such as on this post question page "Add images (optional):"), clicking "Browse" does nothing * File downloads work correctly when set to "Save files to ..." under Settings, but nothing happens when set to "Always ask you where to save files" * No response to "Ctrl + O" open file shortcut Similar questions and solutions: * [https://support.mozilla.org/en-US/questions/1301319 Fixed by reinstalling Firefox] * [https://support.mozilla.org/bm/questions/1039987 Fixed by resetting Firefox] * [https://support.mozilla.org/gl/questions/1288559 Fixed with a restart on a Mac] * [https://support.mozilla.org/en-US/questions/1350420 Fixed by downgrading to Ubuntu 16.04] Things I tried that did not work: * Disabling hardware acceleration * Starting with add-ons disabled * Troubleshoot mode * Clearing startup cache * Clearing cookies and site data * Clearing history * Refreshing Firefox * Creating and using a new profile * Deleting the `xulstore.json` file from the profile directory * Toggling all permissions under Ubuntu Settings > Applications > Firefox to off and then back to on * chmod 777 ~/Downloads * Disabling native file picker "ui.allow_platform_file_picker = false" And finally, what fixed it for me was to go into "about:config" and '''change "widget.use-xdg-desktop-portal.file-picker" from "2" to "0"'''. Credit to [https://old.reddit.com/r/kde/comments/sd1v2a/tip_set_widgetusexdgdesktopportal_to_true_in/ this post] that clued me in. I really hope this saves someone else 2 days of hair pulling and I would appreciate advice from someone more knowledgeable than me on: * Why this fixed the problem * Whether I should be opening a bug report either against Firefox, or Ubuntu * Whether I should also be changing "widget.use-xdg-desktop-portal.mime-handler" and "widget.use-xdg-desktop-portal.settings", both are currently set to "2"