Have you ever been working on a puzzle and a message pops up congratulating you for solving it; while there are still empty spaces in the grid?
Depending on which spaces in the grid you fill in, it's possible to complete the puzzle without checking every box.
The simplest way to avoid this is to leave a green square in the top left corner group empty (or with a red X ❌ in it). Then the puzzle will not finish.
FYI the auto detect works by checking the top row group and the left column group. If either have all their green circles then the puzzle is considered to be solved.
We try not to clutter the app with too many buttons and switches, but are considering an option to disable it.