Performance: Chrome Downloads 2 Poster Images When Crossorigin Attribute (Anonymous) Present on Video

Posted on EST by Michael "Spell" Spellacy

Browser: Chrome 53.0.2785.116 (64-bit)
Operating System: OS X 10.11.5

This issue also present on most stable release of Chrome for Windows.


The poster image on a video element appears to be downloaded twice when a crossorgin attribute with a value of "anonymous" also exists on same element.

This attribute and value are required to get our video captioning to render from our CDN.


<video crossorigin="anonymous" preload="none" poster="" controls>

    <source src="" type="video/mp4">
    <track label="English" kind="subtitles" srclang="en" src="">


Attribute: Present

Attribute: Not Present


About the Author

Michael Spellacy

Michael "Spell" Spellacy is the Director of Accessibility at TMP Worldwide. If you have any questions, feel free to contact him on Github or see what he is up to on Twitter.


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