Linking to media that is hosted on YouTube or Vimeo is a threat to platform and content longevity, especially for media that is owned or managed by third parties. In order to mitigate against future link rot and the general instability of archiving streamed content, where appropriate (technically and legally), host a local copy of any media assets and embed it in the web page using standard HTML5 media tags. In order to keep the overall size of embedded media manageable for access and for the purpose of web archiving, it may be advantageous to embed lower quality copies of the media and link to higher resolution versions via persistent links such as DOIs.
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12. Start discussions about multimedia features early
14. Avoid depending on externally hosted web services