I don't know if this is possible with the current API but I was thinking an add-on that allowed a slash command(s) or hotkey(s) to quickly join a player's home or guest campaigns would be helpful.
Currently I press "L", click on the Campaigns tab, click the type of campaign (7 day, etc) if I even know it (the user sees their campaign names listed but maybe they don't remember that one is "7 day" and the other is "14 day"), right click the campaign, select Join, wait for the notification, open notifications, click on the notification, click the check mark or press "E", then press "E" again to accept.
I will probably feedback this to the devs as well. Thank you!