In my case, Safari was the only major browser playing MP4 to fix the problem that I passed in the JavaScript below that defines Safari and adds the class to the body
if (navigator.userAgent.search("Safari") >= 0 && navigator.userAgent.search("Chrome") < 0) { $('body').addClass('safari'); }
Then in my CSS file I changed the background color to match the background image
body.safari, .safari video, .safari .mantle { background:#3b3b3b; }
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