I think I was hit by the same bug. After trying to reboot the error message changes and I am neither able to install nor to remove the package:
[timwolla@~]sudo snap remove xkcd-webserver error: can't remove "xkcd-webserver": cannot find mounted snap "xkcd-webserver" at revision 15 [timwolla@~ [1]]sudo snap install xkcd-webserver error: can't install "xkcd-webserver": snap "xkcd-webserver" already installed
I think I was hit by the same bug. After trying to reboot the error message changes and I am neither able to install nor to remove the package:
[timwolla@~]sudo snap remove xkcd-webserver
error: can't remove "xkcd-webserver": cannot find mounted snap "xkcd-webserver" at revision 15
[timwolla@~ [1]]sudo snap install xkcd-webserver
error: can't install "xkcd-webserver": snap "xkcd-webserver" already installed