How do I permanently disable notifications about Auto capture keyboard and Mouse pointer integration for a Virtualbox VM?

I have installed Ubuntu 16.04 on a VirtualBox VM. Now every time I boot it, I get two overlay notifications from VirtualBox:

You have the Auto capture keyboard option turned on. This will cause the Virtual Machine to automatically capture the keyboard every time the VM window is activated and make it unavailable to other applications running on your host machine: when the keyboard is captured, all keystrokes (including system ones like Alt-Tab) will be directed to the VM. (...)

and

The Virtual Machine reports that the guest OS supports mouse pointer integration. This means that you do not need to capture the mouse pointer to be able to use it in your guest OS — all mouse actions you perform when the mouse pointer is over the Virtual Machine’s display are directly sent to the guest OS. If the mouse is currently captured, it will be automatically uncaptured.

These overlay notifications persist from the start of boot untill I click ☓ on them.

Can I disable them permanently?

I'm runnung VirtualBox 5.0 on Ubuntu 16.04 (amd64).

2 Answers

To remove the message once: click the X button.

To remove the message once and for all: click the crossed-out balloon next to the X.

To reinstate these messages, go to Settings -> User Interface -> File - Reset all warnings (this is my translation, could be slightly different).

Moving my comment into an answer:

VBoxManage setextradata global GUI/SuppressMessages "all"

You can see a more granular view of the possible values for GUI/SuppressMessages with VBoxManage getextradata global enumerate - mine looked like:

confirmInputCapture,remindAboutAutoCapture,remindAboutMouseIntegrationOff,remindAboutMouseIntegrationOn,remindAboutWrongColorDepth

before I set it to all.

I figured this out from and but apparently all is not documented and was discovered by reading the source.