Comment 99 for bug 18995

(In reply to comment #21)
> And does Fx will use by default the default application setting up in the
> desktop user like with xdg-open?

That may be a different bug. This bug is related to ease of use in choosing an alternative, non-default application. (In that we offer an alternative to the file picker dialog.) If there's a problem on Linux with Fx sending downloaded content to default handlers or if that functionality can be improved, we should spin off a different bug or (if applicable) re-open one of the dupes.