Steps to reproduce:

1. Create a two host groups (test1 and test2).
2. Create a trigger action and add 3 conditions (not suppressed, host group “test1”, and host group “test2”). Use a custom expression and put “A and (B or C)”.
3. Now delete host group “test1”. The trigger action is disabled as expected.
4. Now go to the list of trigger actions and you can enable trigger action from the list page.
5. The trigger action is now enabled with the custom expression of “A and (B or C)” but does not have a condition of “C”.

Result:
Action is enabled with a broken condition expression and wrong results.

Expected:
Do not allow to do this until condition expression is fixed.