[BUG] 第二个视频没有清空第一个视频留下的信息。 #16

[tolerious]

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上一个视频有中英文，下一个视频没有中英文的时候，左边的实时字幕中文还在，最右侧的中文面板没有显示“功能开发中”字样。

https://www.ted.com/talks/tombo_banda_meet_mini_grids_the_clean_energy_solution_bringing_power_to_millions?subtitle=en&language=en

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