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YouTubeのライブチャットの究極のパフォーマンスブースト
< YouTube スーパーファーストチャットについてのフィードバック
In v0.60.0, the ticker renderer's handleLiveChatAction & handleLiveChatActions are amended to resolve the issue. It seems like the YouTube engine's own bug.
Known Bug: Sometimes tickers will be added twice at the same time. Root clause TBC.