Slower by the Afternoon
Decide what you would build from the brief alone. Everything below it is available, but the exercise stops working if you open it first.
An agent console degrades over a working day and occasionally crashes the tab. It cannot be reproduced in a short session. Find the cause and prevent the class.
Finding one component that failed to remove a resize listener, fixing it, watching the synthetic session's memory curve flatten, and closing the ticket. The curve flattened for that cycle, on that route, with that fixture. The console has hundreds of navigation targets and the same cleanup mistake is available in every one of them, so the next feature reintroduces it and the report comes back in a month attributed to something else entirely. The instance was worth fixing; without a structural guarantee — cleanup owned by the boundary that created the subscription, and a memory signal that fails in CI or alerts from the field — the fix is one instance of a defect the codebase will keep producing.