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We are not sure what the “Get embed code” produces, but you can either rip the URL out of there and place it in the iframe macro, or take the whole thing and put it in the Secure HTML macro that we include.
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Can I export iframes content when export pages?
We do not support exporting content from iframes as that would require us to render it server side. We also do not intend to add this functionality.
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Is it possible to have the autoplay attribute removed for the video/mp4 format when using iframe on Confluence?
The autoplay is set by whatever internal server you use to serve the video. So it must be disabled on the source for the Iframe.
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