diff --git a/CHANGELOG.md b/CHANGELOG.md
index a084b56b7..417ed6f06 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,20 @@
+<a name="8.4.2"></a>
+## [8.4.2](https://github.com/videojs/video.js/compare/v8.4.1...v8.4.2) (2023-06-06)
+
+### Bug Fixes
+
+* **loading-spinner:** fix loading spinner responsiveness when default font size is modified ([#8295](https://github.com/videojs/video.js/issues/8295)) ([f075177](https://github.com/videojs/video.js/commit/f075177))
+* **package:** update videojs-contrib-quality-levels to 4.0.0 to eliminate deprecation warning ([#8303](https://github.com/videojs/video.js/issues/8303)) ([fab8f95](https://github.com/videojs/video.js/commit/fab8f95))
+* **shadow-dom:** prevent warning 'element supplied is not included' ([#8192](https://github.com/videojs/video.js/issues/8192)) ([dc1e2bb](https://github.com/videojs/video.js/commit/dc1e2bb))
+* **text-track-settings:** fix text track settings responsiveness when default font size is modified ([#8294](https://github.com/videojs/video.js/issues/8294)) ([3dece50](https://github.com/videojs/video.js/commit/3dece50))
+
+<a name="8.4.1"></a>
+## [8.4.1](https://github.com/videojs/video.js/compare/v8.4.0...v8.4.1) (2023-06-05)
+
+### Bug Fixes
+
+* revert resolveJsonModule in tsconfig ([#8310](https://github.com/videojs/video.js/issues/8310)) ([8f32b9f](https://github.com/videojs/video.js/commit/8f32b9f))
+
 <a name="8.4.0"></a>
 # [8.4.0](https://github.com/videojs/video.js/compare/v8.3.0...v8.4.0) (2023-06-02)
 
diff --git a/package-lock.json b/package-lock.json
index 4be4f8f0b..247c60cee 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "video.js",
-  "version": "8.4.0",
+  "version": "8.4.2",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
@@ -15224,13 +15224,21 @@
               }
             }
           }
+        },
+        "videojs-contrib-quality-levels": {
+          "version": "3.0.0",
+          "resolved": "https://registry.npmjs.org/videojs-contrib-quality-levels/-/videojs-contrib-quality-levels-3.0.0.tgz",
+          "integrity": "sha512-sNx38EYUx+Q+gmup1gVTv9P9/sPs28rM7gZOx1sedaHoKxEdYB+ysOGfHj6MSELBMNGMj6ZspdrpSiWguGvGxA==",
+          "requires": {
+            "global": "^4.4.0"
+          }
         }
       }
     },
     "videojs-contrib-quality-levels": {
-      "version": "3.0.0",
-      "resolved": "https://registry.npmjs.org/videojs-contrib-quality-levels/-/videojs-contrib-quality-levels-3.0.0.tgz",
-      "integrity": "sha512-sNx38EYUx+Q+gmup1gVTv9P9/sPs28rM7gZOx1sedaHoKxEdYB+ysOGfHj6MSELBMNGMj6ZspdrpSiWguGvGxA==",
+      "version": "4.0.0",
+      "resolved": "https://registry.npmjs.org/videojs-contrib-quality-levels/-/videojs-contrib-quality-levels-4.0.0.tgz",
+      "integrity": "sha512-u5rmd8BjLwANp7XwuQ0Q/me34bMe6zg9PQdHfTS7aXgiVRbNTb4djcmfG7aeSrkpZjg+XCLezFNenlJaCjBHKw==",
       "requires": {
         "global": "^4.4.0"
       }
diff --git a/package.json b/package.json
index 8dc0d739f..e32a358f4 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "video.js",
   "description": "An HTML5 video player that supports HLS and DASH with a common API and skin.",
-  "version": "8.4.0",
+  "version": "8.4.2",
   "main": "./dist/video.cjs.js",
   "module": "./dist/video.es.js",
   "style": "./dist/video-js.css",
@@ -52,7 +52,7 @@
     "minify:css:cdn": "cleancss dist/alt/video-js-cdn.css -o dist/alt/video-js-cdn.min.css",
     "minify:css:default": "cleancss dist/video-js.css -o dist/video-js.min.css",
     "watch": "npm-run-all -p watch:*",
-    "watch:lang": "chokidar --initial 'lang/**/!(zh-Hans|zh-Hant)*.json' -c 'npm run build:lang'",
+    "watch:lang": "chokidar --initial \"lang/**/!(zh-Hans|zh-Hant)*.json\" -c \"npm run build:lang\"",
     "watch:rollup": "rollup -c -w --no-progress",
     "watch:types": "tsc -w",
     "watch:css": "npm-run-all -p build:css:default build:css:cdn watch:css:*",
@@ -96,7 +96,7 @@
     "mpd-parser": "^1.0.1",
     "mux.js": "^6.2.0",
     "safe-json-parse": "4.0.0",
-    "videojs-contrib-quality-levels": "3.0.0",
+    "videojs-contrib-quality-levels": "4.0.0",
     "videojs-font": "4.1.0",
     "videojs-vtt.js": "0.15.4"
   },
diff --git a/sandbox/shadow-dom.html.example b/sandbox/shadow-dom.html.example
new file mode 100644
index 000000000..90ea34897
--- /dev/null
+++ b/sandbox/shadow-dom.html.example
@@ -0,0 +1,79 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="utf-8" />
+  <title>Video.js Sandbox</title>
+  <link href="../dist/video-js.css" rel="stylesheet" type="text/css">
+  <script src="../dist/video.js"></script>
+  <link rel="icon" href="data:;base64,=">
+</head>
+<body>
+  <div style="background-color:#eee; border: 1px solid #777; padding: 10px; margin-bottom: 20px; font-size: .8em; line-height: 1.5em; font-family: Verdana, sans-serif;">
+    <p>You can use /sandbox/ for writing and testing your own code. Nothing in /sandbox/ will get checked into the repo, except files that end in .example (so don't edit or add those files). To get started run `npm start` and open the index.html</p>
+    <pre>npm start</pre>
+    <pre>open http://localhost:9999/sandbox/index.html</pre>
+  </div>
+
+  <p>Tap on video to play/pause</p>
+
+  <test-custom-element id="customElement1"></test-custom-element>
+
+  <script>
+    // Custom Element definition
+    class TestCustomElement extends HTMLElement {
+
+      constructor() {
+        super();
+
+        const shadowRoot = this.attachShadow({ mode: 'closed' });
+
+        const styleLinkElem = document.createElement('link');
+
+        styleLinkElem.setAttribute('rel', 'stylesheet');
+        styleLinkElem.setAttribute('href', '../dist/video-js.css')
+        shadowRoot.append(styleLinkElem);
+
+        const containerElem = document.createElement('div');
+
+        containerElem.setAttribute('data-vjs-player', '');
+        shadowRoot.appendChild(containerElem);
+
+        const videoElem = document.createElement('video');
+
+        videoElem.setAttribute('preload', 'auto');
+        videoElem.setAttribute('width', 640);
+        videoElem.setAttribute('height', 260);
+        containerElem.appendChild(videoElem);
+
+        const sourceElem = document.createElement('source');
+
+        sourceElem.setAttribute('src', 'https://vjs.zencdn.net/v/oceans.mp4');
+        sourceElem.setAttribute('type', 'video/mp4');
+        videoElem.appendChild(sourceElem);
+
+        this.innerPlayer = videojs(videoElem);
+
+        containerElem.addEventListener('click', () => {
+          if (this.innerPlayer.paused()) {
+            this.innerPlayer.play();
+          }
+          else {
+            this.innerPlayer.pause();
+          }
+        });
+      }
+    }
+
+    window.customElements.define('test-custom-element', TestCustomElement);
+
+    // Main entry point
+
+    document.addEventListener('DOMContentLoaded', () => {
+      var customElem = document.getElementById('customElement1');
+      var innerPlayer = customElem.innerPlayer;
+      innerPlayer.log('Shadow DOM inner player created', innerPlayer);
+    });
+  </script>
+
+</body>
+</html>
diff --git a/src/css/components/_captions-settings.scss b/src/css/components/_captions-settings.scss
index 8fa89452d..8c36ed82b 100644
--- a/src/css/components/_captions-settings.scss
+++ b/src/css/components/_captions-settings.scss
@@ -53,6 +53,10 @@
 }
 
 // Form elements
+.vjs-text-track-settings select {
+  font-size: inherit;
+}
+
 .vjs-track-setting > select {
   margin-right: 1em;
   margin-bottom: 0.5em;
@@ -65,7 +69,7 @@
 
 .vjs-text-track-settings fieldset span {
   display: inline-block;
-  padding: 0 6px 8px;
+  padding: 0 .6em .8em;
 }
 
 // style the second select for text colors
@@ -76,17 +80,11 @@
 .vjs-text-track-settings legend {
   color: $primary-foreground-color;
   font-weight: bold;
-  font-size: 14px;
+  font-size: 1.2em;
 }
 
 .vjs-text-track-settings .vjs-label {
-  clip: rect(1px 1px 1px 1px); // for Internet Explorer
-  clip: rect(1px, 1px, 1px, 1px);
-  margin: 0 5px 5px 0;
-  border: 0;
-  height: 1px;
-  width: 1px;
-  overflow: hidden;
+  margin: 0 .5em .5em 0;
 }
 
 .vjs-track-settings-controls button:focus,
diff --git a/src/css/components/_loading.scss b/src/css/components/_loading.scss
index 7dbee7da6..a88508431 100644
--- a/src/css/components/_loading.scss
+++ b/src/css/components/_loading.scss
@@ -3,20 +3,20 @@
   position: absolute;
   top: 50%;
   left: 50%;
-  margin: -25px 0 0 -25px;
+  transform: translate(-50%, -50%);
   opacity: 0.85;
 
   // Need to fix centered page layouts
   text-align: left;
 
-  border: 6px solid rgba($primary-background-color, $primary-background-transparency);
+  border: .6em solid rgba($primary-background-color, $primary-background-transparency);
   // border: 6px solid rgba(43, 51, 63, 0.5);
 
   box-sizing: border-box;
   background-clip: padding-box;
-  width: 50px;
-  height: 50px;
-  border-radius: 25px;
+  width: 5em;
+  height: 5em;
+  border-radius: 50%;
   visibility: hidden;
 }
 
@@ -31,7 +31,7 @@
 .vjs-loading-spinner:after {
   content: "";
   position: absolute;
-  margin: -6px;
+  margin: -0.6em;
   box-sizing: inherit;
   width: inherit;
   height: inherit;
diff --git a/src/js/video.js b/src/js/video.js
index 2734cf08d..12a3d8235 100644
--- a/src/js/video.js
+++ b/src/js/video.js
@@ -149,7 +149,12 @@ function videojs(id, options, ready) {
   // This will make sure that the element is indeed in the dom of that document.
   // Additionally, check that the document in question has a default view.
   // If the document is no longer attached to the dom, the defaultView of the document will be null.
-  if (!el.ownerDocument.defaultView || !el.ownerDocument.body.contains(el)) {
+  // If element is inside Shadow DOM (e.g. is part of a Custom element), ownerDocument.body
+  // always returns false. Instead, use the Shadow DOM root.
+  const inShadowDom = el.getRootNode() instanceof window.ShadowRoot;
+  const rootNode = inShadowDom ? el.getRootNode() : el.ownerDocument.body;
+
+  if (!el.ownerDocument.defaultView || !rootNode.contains(el)) {
     log.warn('The element supplied is not included in the DOM');
   }
 
diff --git a/test/unit/utils/custom-element.test.js b/test/unit/utils/custom-element.test.js
new file mode 100644
index 000000000..a60f793da
--- /dev/null
+++ b/test/unit/utils/custom-element.test.js
@@ -0,0 +1,26 @@
+/* eslint-env browser */
+import videojs from '../../../src/js/video.js';
+
+export class TestCustomElement extends HTMLElement {
+
+  constructor() {
+    super();
+
+    const shadowRoot = this.attachShadow({ mode: 'closed' });
+
+    const containerElem = document.createElement('div');
+
+    containerElem.setAttribute('data-vjs-player', '');
+    shadowRoot.appendChild(containerElem);
+
+    const videoElem = document.createElement('video');
+
+    videoElem.setAttribute('width', 640);
+    videoElem.setAttribute('height', 260);
+    containerElem.appendChild(videoElem);
+
+    this.innerPlayer = videojs(videoElem);
+  }
+}
+
+window.customElements.define('test-custom-element', TestCustomElement);
diff --git a/test/unit/video.test.js b/test/unit/video.test.js
index 2b041b9ba..327437b0d 100644
--- a/test/unit/video.test.js
+++ b/test/unit/video.test.js
@@ -4,6 +4,8 @@ import * as Dom from '../../src/js/utils/dom.js';
 import log from '../../src/js/utils/log.js';
 import document from 'global/document';
 import sinon from 'sinon';
+// import custom element for Shadow DOM test
+import './utils/custom-element.test';
 
 QUnit.module('video.js', {
   beforeEach() {
@@ -84,6 +86,29 @@ QUnit.test(
   }
 );
 
+QUnit.test(
+  'should not log if the supplied element is included in the Shadow DOM',
+  function(assert) {
+    const origWarnLog = log.warn;
+    const fixture = document.getElementById('qunit-fixture');
+    const warnLogs = [];
+
+    log.warn = (args) => {
+      warnLogs.push(args);
+    };
+
+    const customElem = document.createElement('test-custom-element');
+
+    fixture.appendChild(customElem);
+    const innerPlayer = customElem.innerPlayer;
+
+    assert.ok(innerPlayer, 'created player within Shadow DOM');
+    assert.equal(warnLogs.length, 0, 'no warn logs');
+
+    log.warn = origWarnLog;
+  }
+);
+
 QUnit.test(
   'should log about already initialized players if options already passed',
   function(assert) {
diff --git a/tsconfig.json b/tsconfig.json
index 46c83a27a..1311702d2 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -8,7 +8,6 @@
     "declarationMap": true,
     "skipLibCheck": true,
     "checkJs": false,
-    "preserveWatchOutput": true,
-    "resolveJsonModule": true
+    "preserveWatchOutput": true
   }
 }
\ No newline at end of file