Flashing textbox in ADV mode when entering or exiting the main menu

[Daniel Wong]

The textbox flashes briefly when entering or exiting the main menu. Not a critical issue, but still annoying.

Afaik this issue is present even in NVL mode, but you can't see it because the the "textbox" color is black, and the the background is also black. The reason you can see it in ADV mode is because the textboxes are colored or have an image on them, so you can see them when overlaid on a black background.

The issue is due to either langen or just a blank text command being shown when you transition into or out of the main menu (I investigated it a bit before). Or perhaps it's because when setwindow is called it automatically shows the textbox? not sure.