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Only one preview link can be added per file.
One preview link can be used more than once.
Available preview sources are YouTube, Vimeo, and also direct links to .webm and .mp4 files. See working examples for .webm and .mp4 file formats respectively:
Links to the file located locally on the user’s machine will not work. The files have to be accessible online.
Keep in mind that only direct links to videos from YouTube, and Vimeo are supported. Unfortunately, channels and short videos are not currently supported. This is an example of how to format the short video to create a URL that works:
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