Using Windows 10 and FMPA 16.0.3
It is extremely annoying the way that the script workspace loses focus after editing a script step. E.g. I am editing the conditions for an If step in the workspace itself (not the calc engine). As soon as you click out of the edit box, the script workspace loses focus and focus jumps to any other window that is open in FM. If one is not careful, you can very easily begin typing, editing, deleting things in this other window before you realize that you are no longer in the script window.
This needs to be fixed. You should not switch windows unless you specifically take action to do so.