I just installed Balena Etcher 1.5.100 on Linux Mint 20.1 x86_64
It worked perfectly flashing a SD card, but now whenever I click an internet shortcut on my desktop, Balena starts up and wants to use it.
In linux this is a .desktop file.
In my settings the default app for this type of file is Firefox, but still Balena wants to use it.
How can I change this?
Hi - this seems to be an issue with xdg settings - and not etcher or Electron - and we’ve had someone report this before. Can you check the workaround mentioned on this issue - Missing parameter in set_url_scheme_handler_gnome3? (#180) · Issues · xdg / xdg-utils · GitLab . Please let us know if this works for you
That was exactly my issue and that trick solved it.
I did this: " sudo vi $(which xdg-settings) "
And then afterwards this: " xdg-mime default firefox.desktop text/html "
In my xdg-settings file it was line 1194. “set_browser_mime “$2” || return”
Thank you for the advice and solution, much appreciated. 
Glad you got it to work Joe! Thanks for sharing the steps that you followed, that certainly will be useful for others!