RFD 1134: A loop notebook is tested in the browser
Problem
The four loop notebooks carried one check. Livebook.LiveMarkdown.Import read each file and reported zero warnings. That check reads the file. It never evaluates a cell.
A run in the browser found the difference. Evaluate all on loop 1 stops at the fit cell, and Python reports ModuleNotFoundError: No module named 'torch'. The setup cell declares pillow, numpy and matplotlib only. The four cells after it stayed queued and never ran.
A queued cell and a passing cell look the same in a screenshot. A silent skip reads exactly like a pass.
Decision
Test a notebook by evaluating it in the browser that serves it. SKILL.md gives the order.
A headed Chromium runs on the desk display. Playwright attaches to that window over a debug port. One window stays open across the steps, so a person watches each cell and takes the keyboard at any point.
Report every cell by name and by state. Name each cell that never ran. Do not average over the cells that did run.
The same run corrected the start command. mix run --no-halt in the dev environment does not boot. MIX_ENV=prod is the command that serves.
See DETAILS.md for the apparatus and the defect in loop 1.