Error: Cannot invoke method minus() on null object

[Freeluv]

@bravenel Receiving the following error when trying to define a required expression. I'm on platform version 2.3.5.101

app:6902023-03-02 12:05:23.712 PMerrorjava.lang.NullPointerException: Cannot invoke method minus() on null object on line 241 (method STPage)

app:6902023-03-02 12:05:15.898 PMerrorjava.lang.NullPointerException: Cannot invoke method minus() on null object on line 241 (method STPage)

[DubbyDad]

See existing thread on this topic:

Error Defining a New Required Expression in RM

OK, this is a new bug. I'll try to get this fixed, and that into a hot fix release... A workaround in a new rule would be to first open the Actions section. That should allow this not to throw the error.