We send out a weekly email with a video from vimeo, but the thumbnail has recently been showing as color bars instead of the thumbnail saved in Vimeo. It's pretty jarring when you look at the email.
Thank you for reaching out to the community! Although you have already spoken with our chat support about this, i would be happy to share our response here as well. This is experience you are having is a defect that our support team is continuing to troubleshoot. There are two workarounds we do suggest. The first being to open the video on Vimeo, copy its link from the share option by clicking the paper plane icon, and inserting this copied share link into a new video block. Our second work around is creating an image of your video and inserting it as a clickable image.