feat: Add Adaptive Buffer-Aware Quality Manager (#3967)#3968
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Bhaumik1904 wants to merge 1 commit into
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feat: Add Adaptive Buffer-Aware Quality Manager (#3967)#3968Bhaumik1904 wants to merge 1 commit into
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communism420
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communism420
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communism420
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Review: Adaptive Buffer-Aware Quality Manager
Overall: Clever approach to a hard problem. The analysis that direct buffer eviction is impossible from an extension is correct, and the quality-throttling alternative is pragmatic.
Good
- Hysteresis band (restore at 60% of ceiling) prevents oscillation
- Guards for paused, live streams, and missing metadata are all correct
- Cleanup path when feature is toggled off restores original quality
- Uses playerQuality() which respects existing quality selection infrastructure
Concerns
- playerQuality(large) hardcodes 480p — May be too aggressive. On a 4K monitor, 480p looks noticeably bad. Consider making throttle quality configurable.
- Called on every 500ms tick — Runs ~14,400 times for a 2hr video. Once throttled, skip checks for N seconds since buffer won't drain instantly.
- Stale quality on manual change — If user manually changes quality while throttled, _sbmQualityBeforeThrottle could be stale. Consider resetting throttle state on manual quality change.
Nit
- Comment says large = 480p but YouTube quality labels vary. A comment referencing the actual itag would be more precise.
Verdict: No blocking issues. Approach is sound for an extension-level workaround.
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Closes #3967
What this does
Implements an alternative to the "Smart Buffer Management" feature requested in #3967.
After feasibility analysis, direct buffer eviction (SourceBuffer.remove()) was confirmed impossible from a browser extension — YouTube owns its MediaSource pipeline internally and does not expose it.
This PR implements the only viable alternative: a quality manager that monitors how many seconds are buffered ahead of the playhead, and temporarily lowers stream quality when it exceeds a configurable ceiling. This prevents unbounded RAM growth on long videos by slowing down YouTube's buffering — the only lever an extension can actually control.
Changes
player.js— NewImprovedTube.smartBufferManager()functionfunctions.js— Hooked intoinitPlayer()andplayerOnTimeUpdate()core.js— Live-toggle support viacase 'smartBuffer':menu/skeleton-parts/player.js— Settings UI (toggle + slider, 30–600s, default 120s)_locales/en/messages.json— English strings added (translations welcome from contributors)How it works
video.buffered