anchor.diff:                          world
                   let world = World.setTickRate 0L world
                   refreshFormOnUndoRedo form world
  -                world)
  +                world
   
       let private handleFormRedo (form : GaiaForm) (_ : EventArgs) =
  -        ignore ^ WorldChangers.Add (fun world ->
  +        addWorldChanger ^ fun world ->
               match (World.getUserState world).FutureWorlds with
               | [] -> world
               | futureWorld :: futureWorlds ->
  
positive.code:                 let world = World.cutToClipboard entityTds.DescribedEntity world
                  deselectEntity form world
                  world
              | _ -> Log.trace ^ "Invalid cut operation (likely a code issue in Gaia)."; world)
  
      let private handleFormPaste atMouse (form : GaiaForm) (_ : EventArgs) =
          ignore ^ WorldChangers.Add (fun world ->
              let world = pushPastWorld world world
              let selectedGroup = (World.getUserState world).SelectedGroup
              let (positionSnap, rotationSnap) = getSnaps form
  
negative.code:                 world
              | Left error ->
                  ignore ^ MessageBox.Show ("Asset reload error due to: " + error + "'.", "Asset reload error", MessageBoxButtons.OK, MessageBoxIcon.Error)
                  world
  
      let private handleFormGroupTabSelected (form : GaiaForm) (_ : EventArgs) =
          addWorldChanger ^ fun world ->
              let world = unsubscribeFromEntityEvents world
              let world =
                  World.updateUserState (fun editorState ->
  