Panel hide() callback
The hide() function is an optional lifecycle method in panel objects. XD calls hide() each time your plugin panel is hidden -- if the user navigates back to the overall plugin list view, toggles to show a different plugin's panel UI, or closes the left-land sidebar altogether. (hide() is not called when the window is closed or XD is quitting, however).
The event argument provides the same event.node object as was passed to your show() callback earlier.
You can choose to remove your UI at the time hide is called, or if you prefer to reuse your UI, you can leave it attached. See the show() documentation page for examples of both approaches.
