Bug: outOfFocusTimeouts array grows unboundedly — cleared timeout ids never removed from array
Author: priyanshu1976Created Aug 26, 2026Updated Aug 26, 2026
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Issue details
Current Behavior
outOfFocusTimeouts in frontend/src/ts/states/test.ts accumulates timeout ids forever:
// states/test.ts:38-54
const outOfFocusTimeouts: (number | NodeJS.Timeout)[] = [];
...
} else {
outOfFocusTimeouts.push(
setTimeout(() => { set(val); }, 1000),
);
}Every unfocus event pushes a new id onto the array. clearTimeouts() (utils/misc.ts:148-153) only calls clearTimeout on each entry but never removes them from the array, so the array grows monotonically for the entire session. Long sessions with frequent alt-tabbing accumulate thousands of stale numeric ids (small but unnecessary retained memory, and the array scan in clearTimeouts grows linearly).
Expected Behavior
Remove consumed entries after clearing, e.g.:
export function clearTimeouts(timeouts: (number | NodeJS.Timeout)[]): void {
timeouts.forEach((to) => clearTimeout(to));
timeouts.length = 0;
}or store only the latest timeout id, since scheduling a newer unfocus supersedes older pending ones anyway.
Steps To Reproduce
- Open devtools memory snapshot / add a breakpoint log on
outOfFocusTimeouts.push. - Blur/refocus the window repeatedly during tests.
- Array length increases without bound and is never reset.
Environment
- OS: Any
- Browser: Any
- Found via source review of
master@ 91bd24bb8
Source: monkeytypegame/monkeytype