[Input Device > Mouse/Touchpad] Mouse highest speed not high enough

[arthurljones]

I use a trackball and have gotten accustomed on all my Linux machines to setting a high mouse movement speed with no acceleration (flat). This allows me to move my cursor with a minimum of thumb motion, which helps reduce joint pain. In Cosmic alpha5, the highest mouse speed setting is about half as fast as I need.

In xf86-based desktop environments, I've managed to increase mouse speed by tuning the device properties with xinput (like Coordinate Tranformation Matrix). However, wayland expects compositors to configure libinput, so xinput does not function. I have tried hand-editing ~/.config/cosmic/com.system76.CosmicComp/v1/input_default to increase speed past the normal max of ~0.6, but this does not seem to increase mouse speed.

I may experiment with udev rules with libinput properties like the calibration matrix and mouse DPI, but it would be fantastic to be able to set what I need in the DE UI. For other users who aren't as technical as me, that may be the only way they can make the change.