I can’t debug the designer so no way to help you. Normally we would want to see what is wrong published. Are you aware you can publish then unpublish to the webflow.io domain?
I was able to see the video even after visiting other pages. Might be your connection?
I’m experiencing the same problem over here. I used the background video widget to play a video on the homepage, but whenever I leave the homepage and go back, the video just displays a white screen. Anybody that can help me fix this problem? Thanks in advance