diff --git a/src/js/controls.js b/src/js/controls.js
index 17d197c5..879fd3fc 100644
--- a/src/js/controls.js
+++ b/src/js/controls.js
@@ -1233,7 +1233,7 @@ const controls = {
         // Inject controls HTML
         if (utils.is.element(container)) {
             target.appendChild(container);
-        } else {
+        } else if (container) {
             target.insertAdjacentHTML('beforeend', container);
         }
 
diff --git a/src/js/fullscreen.js b/src/js/fullscreen.js
index 55b5c804..857a2edc 100644
--- a/src/js/fullscreen.js
+++ b/src/js/fullscreen.js
@@ -193,7 +193,7 @@ class Fullscreen {
         } else if (!Fullscreen.native) {
             toggleFallback.call(this, false);
         } else if (!this.prefix) {
-            document.cancelFullScreen();
+            (document.cancelFullScreen || document.exitFullscreen).call(document);
         } else if (!utils.is.empty(this.prefix)) {
             const action = this.prefix === 'moz' ? 'Cancel' : 'Exit';
             document[`${this.prefix}${action}${this.name}`]();
diff --git a/src/sass/components/sliders.scss b/src/sass/components/sliders.scss
index 62b8d7a9..b9264b05 100644
--- a/src/sass/components/sliders.scss
+++ b/src/sass/components/sliders.scss
@@ -19,7 +19,7 @@
 
     &::-webkit-slider-runnable-track {
         @include plyr-range-track();
-        background-image: linear-gradient(to right, currentColor var(--value), transparent var(--value));
+        background-image: linear-gradient(to right, currentColor var(--value, 0%), transparent var(--value, 0%));
     }
 
     &::-webkit-slider-thumb {