Its started with new QA from 4.4.2.2000 biuld:
If I have local page (file:///D:/Home/MyHome.html) like homepage in Mx and this homepage opened after browser start, I have bug on Youtube - only black space instead of video, no player controls, no flash - I can just listen the audio from that video, but cannot view video itself.
If I minimize Mx window and restore it, after that I can watch video, but - try to scroll this page, and video stay same place on screen and not scrolling!
I found two ways to solve it:
1. You need to press Search button on QA page with empty search line, but it works only until next browser restart - after restart you need to do it again.
2. Choose Homepage with web address (http) instead of local page.
I can see it on Mx 4.4.2.2000, 4.4.3.1000 и 4.4.3.2000 with default options, clean install.
There is no such problem in Mx 4.4.1.3000.
My system: WinXP SP3 (+ all updates), IE8 (+ all updates), Flash Player v.15.0.0.223.
Hope you can fix it.
Information from boss911 user.