I have suddenly found that /usr/games has disappeared off my path. Not only that but my normal otherwise but sudo enabled user seems to have a superuser's path?
What would have changed suddenly? It was not like this yesterday. kpat is in /usr/games and I was able to launch it from task manager yesterday, but not today.
I have rebooted twice so far.
I can run kpat by opening it from Dolphin.
Check your ~/.bash_profile, ~/.bashrc, and ~/.profile files. See if they were modified. You can add those paths (~/bin, /usr/games) to one of those files:
export PATH=$PATH:~/bin:/usr/games
Depending on how you're starting X (assuming X and not Wayland), you could add a line to your ~/.xprofile (or .xsession or .xinitrc) with ". ~/.bashrc" to make sure the path gets set before launching X.
I took a moment to swich back to wayland, and tried "Task Manager" (I was using "Icons only Task Manager") both are showing this issue which is resolved by switching back to X.