Comment 140 for bug 320632

Alistair:

I didn't, there really didn't seem to be any point when I had already determined that the problem was the RightEdge setting spuriously resetting itself to a too-large value.

For the sake of completeness, I tried the Finger{Low,High} setting: it didn't fix the bug. It did allow some edgescrolling, but it was necessary to awkwardly stroke only the extreme edge of the touchpad. Meanwhile, the changed settings made the touchpad awkwardly oversensitive for ordinary pointer movement.

The Finger{Low,High} settings should be left at their current defaults - what needs to be done is to find and fix whatever keeps spuriously resetting the RightEdge value.

I've just done some testing, and I've narrowed down the exact behaviour I observe:

I set a loop of "while sleep 1; do synclient -l | fgrep RightEdge; done" running to monitor the RightEdge value.

Immediately after bootup, the value is 5132. Scrolling *works*! If I very diligently avoid touching the extreme right edge of the touchpad, scrolling continues to work. The moment I touch the extreme right edge of the touchpad, the value printed from the monitor loop changes to 6142. Scrolling now doesn't work, no matter how carefully I touch only the extreme right edge when trying to scroll. I run "synclient RightEdge=5132" - scrolling works again! I touch the right edge - RightEdge reverts to 6142, scrolling no longer works.

Weird.

I hope this means something to someone more familiar with the driver source.