Virtualbox wont start QXcbConnection: XCB error: 3 (BadWindow)

Question

Qt WARNING: QXcbConnection: XCB error: 3 (BadWindow), sequence: 460, resource id: 94371852, major code: 2 (ChangeWindowAttributes), minor code: 0

Qt WARNING: QXcbConnection: XCB error: 3 (BadWindow), sequence: 461, resource id: 94371852, major code: 18 (ChangeProperty), minor code: 0

The only solution i found was to add the environment variable QT_DEVICE_PIXEL_RATIO=1 but this didn't work for me.

Answer 1

You need to set some ENV before launching VirtualBox. Create start script with the following contents:

#!/bin/bash
export QT_SCREEN_SCALE_FACTORS=1
export QT_SCALE_FACTOR=1
export QT_AUTO_SCREEN_SCALE_FACTOR=0
exec virtualbox

Also check, that you have xkeyboard-config and xauth packages installed.