List widget panics with `index out of range[-1]`

i have a goroutine for the UI and a function called from another goroutine to handle keyboard events. i've set it to J to scroll down a list and K to scroll Up, and it saves the row number in a variable, but i randomly get this error which panics the whole program

Start by reproducing the list widget panic while J and K keyboard events are handled from a separate goroutine, then inspect the list scrolling path and its row-index handling. Done means repeated scrolling no longer produces an index-out-of-range panic; the issue names no files or tests to run.

Written by the indexing model from the issue text.