In the page editor (editorial mode), however, the element is not played directly; instead, a simple preview is displayed. The reason for this is that it is more disruptive than helpful during editorial work if, for example, a video is constantly playing.
Switch to preview mode to see how the page will appear online to website visitors.
Modern browsers do NOT support the automatic playback of videos with sound enabled. Therefore, the sound is automatically turned off when a video is played directly.