It's possible to blacklist entities within Picker Dollies to prevent teleportation, to prevent crashes like this.

Edit: Picker Dollies also includes a custom event for responding to its teleportation, though it requires handling the event properly rather than denying it.

I'm surprised there's no (official) event handler for teleportation. Looks like a good case to be made for adding it the API.

Edit2: API request submitted here- https://forums.factorio.com/viewtopic.php?f=28&t=78884

My mod does not do any teleportations, what mod list do you use?

Sorry, to be clear I mean that https://mods.factorio.com/mod/PickerDollies allows players to teleport your entities, causing a crash lua error for the Forcefield logic.

That mod offers two ways to prevent this--one simple, and one more elaborate.

Hopefully the base game will support an official event system to avoid issues like this with all mods, rather than on a case by case basis.

I understand it now. I'll look into it.