Ethos v1.5.7 and X18, X20 series User Manual
Tap on it again, then choose the Channels category and navigate to CH30 (EleCompx)
and select it.
The Butterfly mix is now configured.
Switching to the ‘View by Channel’ view allows you to see the effect of moving the
throttle stick on all the other channels together, which is much easier for debugging etc.