By anticipation, I know that Mozillazine is not Mozilla and not responsible of Firefox.
I never clearly understood which one was the "official" Mozilla forums among this list: mozilla_forums.
If someone knows a developer at Mozilla, he is welcome to provide him the message below.
The file association has never worked correctly in Firefox in a linux/KDE environment.
Firefox is not able to understand the mime types already defined in a system.
This is why ALL mimes need to be redefined for each new profile, and stored in handlers.json file.
Boring, but manageable.
I also never understood why Firefox was always asking again and again to be defined as default browser, although already the default browser.
Code: Select all
$ xdg-settings get default-web-browser
firefox.desktop
As Firefox is not able to understand mimes already defined, in a KDE environment, Firefox (78) now asks to select an application in a pop-up window which is supposed to look in a database called "Discover", which is something totally optional I even have never used, and even did not know what it was.
Now the good news, I know this is a bug already identified by many (to not say all) Gtk applications, long time ago.
Firefox is very likely looking for mimes defined in either '/usr/share/applications/defaults.list' or '~/.local/share/applications/defaults.list', which are obsolete and may be still used by "gnome" / even not sure (see explanations @ April 2012: spacefm/issues)
»»» "xdg-open in its "open-generic" mode uses mimeapps.list, not defaults.list."
The correct default file to be used at user level to look for mimes is ~/.config/mimeapps.list , and nothing else.
It's probably really time to update Firefox to avoid extra mess with some "Discover" specific requirement.
+ more details @ XDG_MIME_Applications