======Event_TabClosed======
This event is sent to the plugin after closing a tab.

The event can be activated/deactivated in the plugin manifest.

===Values===
  * **//(integer) windowhandle//** - Windowhandle of the current GRT main window
  * **//(integer) tabhandle//** - Tabhandle of the closed tab (load file)

===JSON source (example)===
<code>
{
  "Event_TabClosed":{
    "windowhandle":531876,
    "tabhandle":4922491
  }
}
</code>