When the app server is launched and I try e.g to generate database scripts or close the project, IDEA does not manage to kill the process, it is stuck on the below window.
It does that even on a freshly created cuba project.
This bug should have been fixed in the CUBA Studio plugin 12.1 :
Which CUBA plugin version are you using?
Thankq @AlexBudarov ! Upgrading plugin version did indeed solve the issue.
I have probably missed a message asking to upgrade plugin.