Chromium Render SPU tab stuck above VirtualBox task in Win10

Background:

I use Win10 and I run Ubuntu 15.10 on a virtual machine via VirtualBox.

Each time I run the VM, after about 1 hour, another tab is being added to its icon in the Win10 taskbar:

Note the two tabs --- The left is the Chromium Render SPU and the second is the VM with an Ubuntu environment.

My problem:

This Chromium Render SPU tab inhibits my access to the Ubuntu VM. How can I remove it from there so that only the Ubuntu tab appears?

Any workaround or way to solve it will be accepted with much thanks and blessings! :)

Note:

On the Internet, I found the advice to shut down the 3D acceleration, but if I am not wrong, it happened to me even when I disabled 3D acceleration for the VirtualBox Screen Display.

Solution 1:

That's really doesn't answer the question but it seems to have been fixed somehow, maybe via an automatic update (either in VB, Win10, or both, yet I didn't recall encountering such an update in VB):

Throughout the web, I've repeatedly encountered the claim that turning off the 3D acceleration in VB fixed it (IIRC, for me it didn't).

Anyway, For about 7 months now I didn't encounter the problem.

Update - 11/21/2016:

It is indeed unlikely, but if you are using Windows and keep experiencing this problem, and if all you need is the Ubuntu CLI terminal, consider installing Windows Subsystem for Linux (WSL) and using it as your Ubuntu-Bash environment instead. In WSL, as I get it, you use your GPU directly instead of any SPU.