msHorizontalMirror is a read/write property which gets or sets whether a video element is flipped horizontally in the display.

This proprietary property is specific to Internet Explorer and Microsoft Edge.

Boolean value set to true flips the video playback horizontally.

Video perspective is flipped on a horizontal axis - this may be useful for playback of a webcam video, providing the user with better mirroring of their real behaviors (ie. when user moves left, their representation on-screen would move left as well).

       var myVideo = document.getElementById("videoTag1");
       myVideo.msHorizontalMirror = true;
       myVideo.play();

Example #2:

    var flip = document.querySelector('#flip');
    flip.addEventListener('click', function() {
      video.msHorizontalMirror = true;
    });

• HTMLVideoElement
• Microsoft API extensions