Can't leave an unloading trailer/machine

[_Loon-]

- PC/Mac/PS4/XB1: PC
- Vehicle/Tool/Model/Object: Any trailer
- Issue: Cannot start unloading a trailer and then leave it (by "tab-ing") without it stopping the unload.
- Single- or Multiplayer: Singleplayer
- Steps to reproduce: Try unloading any trailer at any sell location
- Does it happen on a standard map without mods yes/no: Yes

I do not know if this is supposed to be like this, but if so, I don't see why.

[jamesadams933]

Happens on Xb1 as well, In my silos and same with forage wagons.