root@irc-bouncer:~# sudo add-apt-repository ppa:mamarley/quassel
 The latest stable release of the Quassel IRC core, client, and monolithic build.
 More info: https://launchpad.net/~mamarley/+archive/ubuntu/quassel
Press [ENTER] to continue or Ctrl-c to cancel adding it.

Ign:1 http://ppa.launchpad.net/mamarley/quassel/ubuntu focal InRelease
Hit:2 http://archive.ubuntu.com/ubuntu focal InRelease
Hit:3 http://archive.ubuntu.com/ubuntu focal-updates InRelease
Hit:4 http://ppa.launchpad.net/mamarley/quassel-git/ubuntu focal InRelease
Hit:5 http://archive.ubuntu.com/ubuntu focal-security InRelease
Hit:6 http://ppa.launchpad.net/thomas-schiex/blender/ubuntu focal InRelease
Err:7 http://ppa.launchpad.net/mamarley/quassel/ubuntu focal Release
  404  Not Found [IP: 91.189.95.85 80]
Reading package lists... Done
E: The repository 'http://ppa.launchpad.net/mamarley/quassel/ubuntu focal Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.