explorer: start menu doesn't always close as it should

Created an attachment (id=5271)
Click on explorer window #1 and Start menu stays open

r48536, Vmware 6

Preparation, see screenshot:

• Start reactos
  Open a few windows:
• Open explorer window #1 using the taskbar. Same explorer process as desktop
• Start cmd.exe (window #2)
• Open explorer window #3 using the cmd prompt this should be a new explorer process

The bug:

• Click on "Start", but don't select an item. Instead, click on the desktop space. The start menu closes (OK)

• Repeat this, but now click on the titelbar or menubar of window #1. The start menu now remains open (NOT OK), see screenshot.
• Repeat this for the client area of window #1. The start menu closes (OK)

• Try the same for window #2 and #3 (any area). The start menu closes (OK)

It only occurs for windows of the desktop explorer process, including the MDI child windows. And only on the window decoration areas: titlebar, menubar, scrollbars, edges but not the client area or status bar.

I cannot reproduce this on Windows XP.