--- a/toolkit/content/widgets/videocontrols.xml
+++ b/toolkit/content/widgets/videocontrols.xml
@@ -1085,28 +1085,49 @@
 
                 onFullscreenChange: function () {
                     if (this.isVideoInFullScreen()) {
                         Utils._hideControlsTimeout = setTimeout(this._hideControlsFn, this.HIDE_CONTROLS_TIMEOUT_MS);
                     }
                     this.setFullscreenButtonState();
                 },
 
+                clickToPlayInteractWithElement : function() {
+                    // First time here, do play and pause now to simulate user
+                    // interaction.
+                    if (this.video.paused || this.video.ended) {
+                        this.video.playbackRate = this.video.defaultPlaybackRate;
+                        this.video.play();
+                        this.video.pause();
+                    } else {
+                        this.video.pause();
+                        this.video.playbackRate = this.video.defaultPlaybackRate;
+                        this.video.play();
+                    }
+                    // Future calls will do nothing.
+                    this.clickToPlayInteractWithElement = function() {};
+                },
                 clickToPlayClickHandler : function(e) {
                     if (e.button != 0)
                         return;
                     if (this.hasError() && !this.suppressError) {
                         // Errors that can be dismissed should be placed here as we discover them.
                         if (this.video.error.code != this.video.error.MEDIA_ERR_ABORTED)
                             return;
                         this.statusOverlay.hidden = true;
                         this.suppressError = true;
                         return;
                     }
 
+                    // If not already started, send a quick play (and pause),
+                    // so the media element thinks user interaction has happened
+                    // when calling play() again in the timeout below (otherwise
+                    // media.autoplay.enabled==false might block it).
+                    this.clickToPlayInteractWithElement();
+
                     // Read defaultPrevented asynchronously, since Web content
                     // may want to consume the "click" event but will only
                     // receive it after us.
                     let self = this;
                     setTimeout(function clickToPlayCallback() {
                         if (!e.defaultPrevented)
                             self.togglePause();
                     }, 0);