I'm seeing a weird problem with scrollbars, both in rich text editors and listboxes. The scrollbars work fine normally so I know the SetMopParent chain is correct. If I hit the Options key it brings up the menu and changes the scrollbar. If I hit Cancel the menu goes away as expected, but the scrollbar goes away and doesn't come back! Scrolling still works as expected, it just doesn't update the arrows. You can actually notice it flashing the scrollbar on the screen for a split second after hitting cancel before it disappears. I looked at the examples where I don't see this behavior, and I don't really see any difference in the code.

Does anyone have any clues?