Bug? opendialog leaves phantom window in jitter's fullscreen mode

I've noticed a strange problem with jitter and opendialog, I think ever since MAX6.

If I interact with the opendialog object and later bring my jitter patch into fullscreen mode, a new window appears along the bottom of the screen. When I exit fullscreen mode it stays there. It's only a few pixels tall and it's set to stay on top.

Anybody else seen this? I attached a screengrab and a simple patch to reproduce.

(MAX 6.1.9 on Mac OS 10.9.5)
-Zach