anchor.diff:                      { editorState with SelectedGroup = stog Simulants.EditorScreen !!groupTab.Text })
                       world
               let world = subscribeToEntityEvents form world
  -            deselectEntity form world
               refreshPropertyGrid form world
               refreshTreeView form world
               world
  
positive.code:         form.quickSizeToolStripButton.Click.Add (handleFormQuickSize form)
          form.resetCameraButton.Click.Add (handleFormResetCamera form)
          form.reloadAssetsButton.Click.Add (handleFormReloadAssets form)
          form.groupTabs.Selected.Add (handleFormGroupTabSelected form)
          form.rolloutTabControl.SelectedIndexChanged.Add (handleRolloutTabSelectedIndexChanged form)
          form.createEntityComboBox.SelectedIndexChanged.Add (handleCreateEntityComboBoxSelectedIndexChanged form)
  
negative.code:                 ignore ^ MessageBox.Show ("Asset reload error due to: " + error + "'.", "Asset reload error", MessageBoxButtons.OK, MessageBoxIcon.Error)
                  world
  
      let private handleFormGroupTabDeselected (form : GaiaForm) (_ : EventArgs) =
          addWorldChanger ^ fun world ->
              let world = unsubscribeFromEntityEvents world
              deselectEntity form world
              refreshPropertyGrid form world
              refreshTreeView form world
              world
  
      let private handleFormGroupTabSelected (form : GaiaForm) (_ : EventArgs) =
          addWorldChanger ^ fun world ->
              let world =
                  World.updateUserState (fun editorState ->
                      let groupTabs = form.groupTabs
  