mistranslation: 0.959 other: 0.864 device: 0.784 socket: 0.684 semantic: 0.670 network: 0.651 instruction: 0.557 vnc: 0.455 boot: 0.376 graphic: 0.352 assembly: 0.185 KVM: 0.031 -display accepts "none[a-z,0-9]*" instead of 'none' When using the '-display' option the parameter 'none' is not the only string that causes the behaviour of 'none'. I can use '-display noneMICKEYMOUSE' and still have the none behaviour. Fixed in: https://git.qemu.org/?p=qemu.git;a=commitdiff;h=2c9498c3e44cd5574