Hello @REINM ,
Is this occurring with a Vimeo video? Is the link you're using the explicit Share option for the video? If using that explicit link, or using the Vimeo integration aren't resolving the colored lines issue, does setting a new / different thumbnail for your Vimeo video, then re-adding the share link get rid of the colored lines? Otherwise if the issue persists with that video, you may just have to screencap the thumbnail of the video, and insert it as an image, then link to that image as the last workaround.
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