Set Gomuks as XDG matrix:// handler

[Evidlo]

I was figuring out how to set up XDG protocol handlers, so I'll document that here.

~/.local/share/applications/matrix-handler.desktop

[Desktop Entry]
Type=Application
Name=Matrix Scheme Handler
Exec=gomuks join %u
StartupNotify=false
MimeType=x-scheme-handler/matrix

~/.local/share/applications/mimeapps.list

[Default Applications]
x-scheme-handler/matrix=matrix-handler.desktop

And finally

$ update-desktop-database ~/.local/share/applications/

Gomuks would need some mechanism to send a /join to an already running instance.

[tulir]

Blocked on matrix-org/matrix-doc#455

[tulir]

matrix-org/matrix-doc#2312 is starting to be ready enough that it can be implemented

[MayeulC]

Shouldn't be blocked anymore, and there has been some activity on the browser front recently, so the scheme might become more relevant soon.