Perhaps https://flatpak.github.io/xdg-desktop-portal/docs/doc-org.fr... ? From a quick skim of the page it's not immediately obvious if that actually will allow PTT to work, though; I'm only suspecting that because I don't see any of its siblings that would even conceivably allow for PTT.
No clue if it's possible or not. I was not able to find any way to do it when I last checked around a year ago, but maybe something has changed since then, or maybe it just isn't implemented in Firefox yet.
[–] chandlerswift 2 days ago
[–] saghm 12 hours ago