Stylus drawing issue with ELAN sensor

Hello,

I'm trying to resolve an issue with the stylus on my HP Spectre x360 Convertible 13-ac0XX laptop using an ELAN 0732 04F3:24DB sensor.

Drawing with the stylus (in eg xournal, gimp) often causes extra lines to appear where they shouldn't. It's a bit hard to explain, but starting a touch with the stylus causes an extra line to be drawn to the touch position from the current cursor position (the cursor lags behind the physical stylus location quite a bit when moving quickly).

I've tried lots of drawing apps and they all have the same behavior though, so I'm guessing the issue is lower-level than the apps themselves. Switching to the evdev driver instead of libinput works around the issue though, so that suggests perhaps libinput is responsible.

This issue in the libwacom project has a file with a ton of diagnostic info about my system. Let me know if you need any more info, or if you need me to test something. I'm happy to help.