Ubuntu shutting down significantly longer when Guayadeque is open

[chemicalkosek]

There is in an issue when shutting down Ubuntu (20.04, but I think had it in previous versions too).
Shutdown takes longer, like 30 seconds or more. Just nothing happening.
I have narrowed it down to Guayadeque, because when I close Guayadeque during the prolonged shutdown process, the system shutdowns immediately.
I don't know how should I provide more info for you, so let me know if you need anything.