Graphics.DrawTexture() + posteffect + zooming a page in browser == dissapearing bug

I use Graphics.DrawTexture() in OnGUI() to draw a round minimap (material used is MaskedTexture from wiki).
There’s also Glow posteffect on my camera. On several computers (but not all),
when I zoom (Ctrl+mouse scroll) my browser (Chrome, Firefox, IE),
my masked texture dissapears from the screen and renders no more. I suspect this is a bug).

I think this is most likely a bug, although it doesn’t seem to have been reported yet. Please can you file a report for this (menu: Help > Report A Bug).

I submitted it a while ago (Case 377250).

Just to be sure I’ve reported it one more time.