Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
The appendWindowStart property of the SourceBuffer interface controls the timestamp for the start of the append window, a timestamp range that can be used to filter what media data is appended to the SourceBuffer. Coded media frames with timestamps within this range will be appended, whereas those outside the range will be filtered out.
The default value of appendWindowStart is the presentation start time, which is the beginning time of the playable media.
