Bug: Main L4 window changes size when using taskbar (still)

Main Screen not being restored to full screen from taskbar.
This was reported in 4.0aB3 http://wiki.logos.com/Bug$3a_Main_Screen_not_being_restored_to_full_screen_from_taskbar and was tagged as being fixed in B4.
But it is still persistent in B4. In the thread below i’ve added a short video clip which shows the problem.

Software version: 4.0a Beta 4.
Reported by Steve Clark.
Forum link: http://community.logos.com/forums/t/6846.aspx
Status: fixed in 4.0a Beta 5