Cannot enable three-finger drag via Marco (accessibility feature)

[foxwhat]

Libinput 1.28 now supports three finger drag (i.e an accessibility feature that uses dragging three fingers as an equivalent to click and drag) but I cannot find a way to turn it on.

I have been told I should enable it via compositor settings but there is no setting in the compositor I can find. I assume it needs to be added and doesn't exist yet because it's a relatively new feature.

Please can you add a way to enable this feature.

https://gitlab.freedesktop.org/libinput/libinput/-/merge_requests/1042

(Debian 13, Mate, Marco, x11)

[lukefromdc]

I'll have to leave this for someone on the team who has hardware that supports this. I have neither a touchscreen monitor nor a laptop with a touchpad that actually works, not sure which case this is meant for