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Such files are not removed after downloading: if the same fragment is requested again, server will send the existing file.
Since build 5.2.899 partial download and playback is supported for audio only recordings too.
Known limits
1. A partial download and playback is supported for MP4 container only. If webm file is requested, it will be always fully downloaded and played.
2. A partial download and playback is not supported for audio only streams. Such recordings will be always fully downloaded and played.3. Playback can start slightly earlier if start time is set, depending on closest key frame in the recording file.
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