Your title says it all for me... Appimage of Firefox. You will need to test the same steps in Firefox from Mozilla to prove that it's a Mozilla issue, but you should already know it's not because Mozilla did not create the appimage. For this issue I feel you'll need to talk to this guy... https://discourse.appimage.org/t/firefox-appimagehub/1846 Try downloading Firefox from Mozilla, unzip, and run firefox-bin from the folder and see if you have the same issue. https://www.mozilla.org/en-US/firefox/all/#product-desktop-release I also use an appimage of LibreOffice because it fails to work normally for me sometime on openSUSE.