Bug: outOfFocusTimeouts array grows unboundedly — cleared timeout ids never removed from array

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Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
84/100
Issue type
Bug
Clarity
Clearly specified
Activity status
Active
Tech stack
typescript
Domain
frontend, performance

Research direction

Start in frontend/src/ts/states/test.ts, where outOfFocusTimeouts is populated, and inspect utils/misc.ts:148-153, where clearTimeouts handles the entries. Trace the callers to confirm whether clearing all stored IDs or retaining only the latest ID preserves the intended blur/refocus behavior. Done means cleared timeout IDs are no longer retained and repeated unfocus/refocus events no longer grow the array indefinitely.

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Description

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Does the issue happen when logged in?

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Yes

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
  1. Open devtools memory snapshot / add a breakpoint log on outOfFocusTimeouts.push.
  2. Blur/refocus the window repeatedly during tests.
  3. Array length increases without bound and is never reset.
Environment
  • OS: Any
  • Browser: Any
  • Found via source review of master @ 91bd24bb8
Dominant language
TypeScript
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