Implemented elapsed counter

multiplayer.js

@@ -258,6 +258,9 @@
             // list of stream overlay icons for play/pause
             this._overlayPlayIcons = [];
 
+            // the periodic task that updates progress bar etc.
+            this._progressInterval = null;
+
             // prepare shadow root
             this.attachShadow({'mode': 'open'});
             this.shadowRoot.appendChild(style.content.cloneNode(true));
@@ -632,6 +635,7 @@
 
             this.setActivePlaylistItem();
             this.autoBlurControls();
+            this.updateProgress();
         }
 
         /*
@@ -890,6 +894,18 @@
             this._mainStream = newMain;
             this.syncStreams();
         }
+
+        updateProgress() {
+            if(this._progressInterval != null) {
+                window.clearInterval(this._progressInterval)
+            }
+            const trackedVideo = this._mainStream.querySelector('video');
+            this._progressInterval = window.setInterval(
+                () => {
+                    this._elapsed.textContent = this.formatTime(
+                        trackedVideo.currentTime);
+                }, 200);
+        }
     }
 
     customElements.define('multi-player', MultiPlayer);