I've installed ksuperkey via cloning from git and compiling with make. Now when I run "apt update" it has an error:
username@osboxes:~$ sudo apt update
Hit:1 http://us.archive.ubuntu.com/ubuntu bionic InRelease
Hit:2 http://us.archive.ubuntu.com/ubuntu bionic-updates InRelease
Hit:3 http://us.archive.ubuntu.com/ubuntu bionic-backports InRelease
Ign:4 http://ppa.launchpad.net/mehanik/ksuperkey/ubuntu bionic InRelease
Hit:5 http://security.ubuntu.com/ubuntu bionic-security InRelease
Err:6 http://ppa.launchpad.net/mehanik/ksuperkey/ubuntu bionic Release
404 Not Found [IP: 91.189.95.85 80]
Reading package lists... Done
E: The repository 'http://ppa.launchpad.net/mehanik/ksuperkey/ubuntu bionic 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.
username@osboxes:~$
I don't care to update this ksuperkey item and want to just "apt update" everything else. I found a similar posting "What can I do if a repository/PPA does not have a Release file?" that I got to through Updating from such a repository can't be done securely [duplicate]. And I tried to ppa-purge the mahnik/ksuperkey, but that hasn't worked:
username@osboxes:~$ sudo ppa-purge ppa:mehanik/ksuperkey
Updating packages lists
E: The repository 'http://ppa.launchpad.net/mehanik/ksuperkey/ubuntu bionic Release' does not have a Release file.
Warning: apt-get update failed for some reason
username@osboxes:~$
In summary, How can I get rid of this "mahanik/ksuperkey doesn't have a Release file, Can't update from securely" error to ensure my "apt update" works?