When the menu is first generated, both from the panel-plugin and the desktop, it will show the scroll-buttons sometimes even though there is enough screen real-estate to display the entire menu. But it won't do this the second time. This seems to happen when the generated (sub-)menu touches the bottom of the screen.
I have checked it again, and this is what seems to happen: 1. The (sub-)menu is generated 2. The (sub-)menu is shown (at this point the menu either touches the bottom of the screen, or it doesn't) 3. The images are loaded (when the menu touched the bottom of the screen at the previous step, it will now add scroll-buttons)
Created attachment 1279 A screenshot of the menu popping up from the panel. This seems to be a gtk issue, not xfdesktop. I have gtk 2.10.13, and it seems to calculate the menu size before the icons are loaded. When the icons are loaded and the items are realized, they won't fit inside the space allocated for them. Gtk won't move the top of the menu up, it only expands downwards. This way it won't fit the screen and as a result, the sliders are shown. This would explain why the menu pops-up correctly a second time.
Is this fixed now? I haven't seen this problem in a while...
We must have fixed this... I haven't seen it in forever.