snap refuses to launch applications

Solution 1:

These steps help me resolve permanently my problem:

• Remove snapd: sudo apt purge snapd snap-confine

• Update: sudo apt update

• Reinstall it: sudo apt install snapd

• Check apparmor's status: systemctl status apparmor

• If status inactive, then activate it: systemctl start apparmor

• Now install any app you want via snap commands line

Remember, you must check and activate apparmor before installing any app.

Solution 2:

The other answers make us uninstall the snap that subsequently removes all the apps installed via snap. This can be a problem if there are many apps installed via snap (as in my case). Easier fix is to check the status of apparmor via

sudo systemctl status apparmor

and then restart the service via

sudo systemctl restart apparmor