bitvid/decisions/DECISIONS_2026-02-15_perf_explore_data.md

Decisions: Explore Data Service Performance Optimization

Decision 1: Gate intervals with document.hidden

Context: setInterval runs unconditionally. Choice: Add if (document.hidden) return; at the start of the interval callback. Rationale: Simple, effective way to stop processing. clearInterval / setInterval on visibility change is more complex to manage state.

Decision 2: Add visibilitychange listener

Context: If we skip updates, data becomes stale. Choice: Listen for visibilitychange. If visible, call refreshWatchHistoryTagCounts() and refreshTagIdf(). Rationale: Ensures that when the user returns, they see fresh data immediately (or very soon). The existing refresh... methods already handle debounce/staleness checks, so calling them is safe.