Authorization Code flow partially implemented

[thibaultamartin]

⚠️ Please try to fill in every blank. Keep the information clear and concise.

What should happen:

The authorization code should not be copied manually. The application should register the following redirect_url comgithubbleakgreytootle://dummy.tld and add a MimeType=x-scheme-handler/comgithubbleakgreytootle; in its desktop file to be "called" when the authentication is complete in the users’s browser.

Parsing the URL passed as an argument will then allow you to retrieve the authorization code.

See a similar issue for Giara for additional help, or ask for help in #gnome-hackers on Matrix/IRC :)

What happened instead:

Mastodon instance displays authotization code which is then expected to be typed in the app

How to reproduce:

Login to a new instance