Opening links in any desktop app to open up in Nightly is broken for me since a few months, I didn't really change anything on my side. The bug report so far has been ignored, and this is a pretty major breakage. Does anyone have an idea what I could check out on my system to get this fixed or provide info for the bug so that somebody actually looks at it? EDIT: Please note Nightly initially launches fine, SO THERE IS NO PROBLEM OPENING THE PROFILE. There is also no problem with a previous instance being stuck preventing the new one from launching - I don't want to launch a new instance, I want to open a link, and I can interact with the running instance just fine and it's definitely not stuck. This is what I get 50% of the time I try to open a link: "Close Firefox" "Firefox is already running, but is not responding. To use Firefox, you must first close the existing Firefox process, restart your device, or use a different profile." (While firefox is perfectly happily running.) xdg-open https://same-url-iclicked works. So that makes it even weirder. My system is a boring Fedora 32 desktop, and I didn't change anything I could think of when this suddenly broke. Here is my two months old ticket that so far went ignored: https://bugzilla.mozilla.org/show_bug.cgi?id=1645038