Test Agent does not show the browser screenshot after idle for a while


I have a private instance.
For the test machine, I installed the virtual box on a linux machine. Then created a Windows 8 VM in virtual box. The WPT agent is running well on this Windows 8 when I have a connection(VNC to the Linux server viewing the Windows 8 desktop). But when I close my VNC connection, let the test machine idle for a while(ex: 30 mins), run the WPT test again using this agent, the screenshot does not show the browser pages, it just shows the Window desktop (as attached image file).

But if I have the WPT test keeps running different tests(no idle or idle less than few mins between each test) on this agent even I close the VNC connection, the screenshot looks fine. Is there anything I need to adjust with in the test machine? Thanks,


Make sure you turn off the screen saver and set power management to never put the screen to sleep. What you are describing sounds very much like the display going to sleep.

Yes, it works by setting the power management to never sleep. Thanks! Jimy