Listbox resize autoscroll sampler

This page reproduces an unwanted scroll jump while resizing a <select multiple> listbox.

The listbox starts at scrollTop=0. During a resize drag, old behavior could enter listbox drag-selection/autoscroll logic and increase scrollTop.

1. Click Reset scrollTop so the listbox starts at the top.
2. Drag the listbox resize handle from bottom-right toward down-right.
3. Check the status and event log.

Reset scrollTop Clear log

(empty)

scrollTop stays 0 while resizing.

scrollTop jumps to a positive value during resize drag.