screen locks in host OS, despite actively working in fullscreen guest OS

[sf_basilix]

I am running Ubuntu 12.04 (64 bit) as the host OS and Windows 7 (64 bit) as the guest OS (in fullscreen mode). If I work long enough in the Windows 7 environment and then go back to my host OS (using cube rotate in compiz), the host OS presents my desktop for 1-2 seconds and then locks the screen with a password lock screen. Once I enter my password, the screen is then unlocked and I can proceed to work in Ubuntu.

This is easily repeatable and was not the case when running Windows XP (32 bit) as a guest OS on Ubuntu 10.04 (64 bit host OS). Previous releases kept the host OS from locking, despite working in the guest OS. If no actions were taking place in the guest OS, then the host OS would lock, after the predetermined time period for locking a screen would pass.

[mpfj]

Affects me too !!

Any update on when it might be fixed ?

It's REALLY annoying.

[Frank Mehnert]

No ETA known. The problem with such changes it that it must work for a couple number of hosts we support. And at least on X.org there are several different APIs handling the screensaver so this is not a one-liner.

[aeichner]

Please reopen if still relevant with a recent VirtualBox release.

[Andrew Schulman]

I have this problem with Virtualbox 5.1.18-114002~Ubuntu~xenial, Ubuntu xenial x86_64 host, Windows 7 64-bit guest. It's exactly as the OP reported: after working in the guest for a while, when I click outside of the guest window, there's a pause of a second or two, and then the OS lock screen kicks in. I have to enter my password to get back to the host OS.