HTML5 - fixes fullscreen toggle to un-fullscreen

bigbluebutton-html5/imports/ui/components/nav-bar/settings-dropdown/component.jsx

@@ -51,22 +51,32 @@ const toggleFullScreen = () => {
   if (document.fullscreenEnabled
     || document.mozFullScreenEnabled
     || document.webkitFullscreenEnabled) {
-    if (element.requestFullscreen) {
-      element.requestFullscreen();
-    } else if (element.mozRequestFullScreen) {
-      element.mozRequestFullScreen();
-    } else if (element.webkitRequestFullscreen) {
-      element.webkitRequestFullscreen();
-    } else if (element.msRequestFullscreen) {
-      element.msRequestFullscreen();
-    }
-  } else {
-    if (document.exitFullscreen) {
-      document.exitFullscreen();
-    } else if (document.mozCancelFullScreen) {
-      document.mozCancelFullScreen();
-    } else if (document.webkitExitFullscreen) {
-      document.webkitExitFullscreen();
+
+    // If the page is already fullscreen, exit fullscreen
+    if (document.fullscreenElement
+      || document.webkitFullscreenElement
+      || document.mozFullScreenElement
+      || document.msFullscreenElement) {
+
+      if (document.exitFullscreen) {
+        document.exitFullscreen();
+      } else if (document.mozCancelFullScreen) {
+        document.mozCancelFullScreen();
+      } else if (document.webkitExitFullscreen) {
+        document.webkitExitFullscreen();
+      }
+
+    // If the page is not currently fullscreen, make fullscreen
+    } else {
+      if (element.requestFullscreen) {
+        element.requestFullscreen();
+      } else if (element.mozRequestFullScreen) {
+        element.mozRequestFullScreen();
+      } else if (element.webkitRequestFullscreen) {
+        element.webkitRequestFullscreen();
+      } else if (element.msRequestFullscreen) {
+        element.msRequestFullscreen();
+      }
     }
   }
 };