Hibernate command as given doesn't work in Ubuntu

[fridgecow]

echo disk | sudo tee /sys/power/state

The type cover backlight stays on suggesting the laptop is still on, and it requires me to do a complete power-cycle (full 10ish seconds on power button) to get it back, and without hibernated state.

I know this is not for Ubuntu but everything else worked, thank you very much for your hard work!