How did they do that?

[diablo75]

Forgive me for lacking a link to the video, but I saw a video on Youtube that showed Ubuntu running with Windows.... Hard to describe. I'll try it like this:

Start with Windows in a virtual machine. Subtract the window borders around the VM. Now make Windows wallpaper and desktop icons invisible, so the Ubuntu desktop is now visible, but you still have the start menu and task bar. .... Anybody know what I'm trying to think of?

[solar george]

Use virtual box and select seamless mode from the (file?) menu when windows is running

[diablo75]

I've actually tried seemless mode with Virtual Box before.... but I didn't know what it did.

The very first time I tried this, it seemed to just go into this fullscreen mode, no Ubuntu to be seen. I had to use LeftCTRL-L to get out. Now when I do it, it seems to attempt to go back into that previous fullscreen mode, but the whole desktop (VM) locks up, no mouse movement, until I exit seemless mode with the same keyboard shortcut mentioned above.

What should I do to try and get it to work correctly?