Choose Default Web Browser for Opening a Link from Terminal
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So, you have set your default browser to be LibreWolf, but when
you right-click a hyperlink and choose to open it in browser the 
window manager opens it in Firefox?
There is more than one default browser.
Yesterday I found on the web that the other default browser can be set
using the "gio" command by typing the following 2 commands:

  gio mime x-scheme-handler/http librewolf.desktop
  gio mime x-scheme-handler/https librewolf.desktop

If you are interested, you can also open files with the default apps by 
typing the command:

  gio open <LOCATION>

where "<LOCATION>" is to be replaced by a file name or a URL.
Use it from a script instead of specifying a browser name.

GIO has more commands similar to the shell commands.  you can view them by 
typing:

  man gio

Their site is:

  https://www.gtk.org/

And guess what? You can get a binary for systems other from Unix/Linux.