Trigger action when click graph without clicking object

[lynn0032]

I've used a triggerSet/updateValue to make buttons appear when a point is clicked in the graph. I would like to make the buttons disappear when the user clicks anywhere else in the graph. A simple-ish solution could be to allow triggerWhenObjectsClicked="g", where "g" is the name of the graph itself.

Here is the minimal DoenetML for this:

<boolean name="hideButtons">true</boolean>

<graph name="g">
  <point name="p"/>
</graph>

<updateValue triggerWhenObjectsClicked="p" target="hideButtons" newValue="false" type="boolean"/> 

<!-- it would solve the issue if this worked -->
<updateValue triggerWhenObjectsClicked="g" target="hideButtons" newValue="true" type="boolean"/>