Alt-Return keyboard short cut does not work immediately

For a while I have some problem with Alt-Return.

• Add 'int x;' to any class (it was DockerDevice in my case, but this does not seem to matter)
• put cursor on x
• Press Alt-Return to get the hotfix menu containing Generate Setter/Getter

-> does not work for me

• Now, go to the class name in the class definition
• Press Alt-Return to get the hotfix menu
• Do not select anything, instead press Esc
• go back to the x
• Press Alt-Return to get the hotfix menu containing Generate Setter/Getter

-> now it works.

Something similar seems to happen when changing a function signature. Alt-Return does not work, however, the light bulb is there and works.