Actions Already Set Prevent Context Hiding

[Enthalpy]

If a frame already has an action on it when the frame is merged/unmerged, the list of permissible actions does not update with the frame's merged status. For instance, merging a frame, giving it a random action, and unmerging it prevents you from setting a Game Over on that frame. Giving the frame a random action and then merging it allows it to pick from any action.

Implications of the invalid trial data are not known.

[Enthalpy]

Additional testing has revealed that the reported reproduction instructions were incorrect: You don't need the frame to have an action on it, but for the "Confirm" button to be pressed.

[Enthalpy]

Fixed by pull request #39.