A youtube video beágyazásánál mit takar a radio_start?

radio_start-ról nem igazán értekezik a hivatalos dokumentáció:

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start van:

"start

This parameter causes the player to begin playing the video at the given number of seconds from the start of the video. The parameter value is a positive integer. Note that similar to the seekTo function, the player will look for the closest keyframe to the time you specify. This means that sometimes the play head may seek to just before the requested time, usually no more than around two seconds."

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