diff --git a/src/apps/stable/features/playback/constants/subtitleStylingOption.ts b/src/apps/stable/features/playback/constants/subtitleStylingOption.ts
new file mode 100644
index 0000000000..bf524ae16f
--- /dev/null
+++ b/src/apps/stable/features/playback/constants/subtitleStylingOption.ts
@@ -0,0 +1,13 @@
+/**
+ * Options specifying if the player's native subtitle (cue) element should be used, a custom element (div), or allow
+ * Jellyfin to choose automatically based on known browser support. Some browsers do not properly apply CSS styling to
+ * the native subtitle element.
+ */
+export const SubtitleStylingOption = {
+    Auto: 'Auto',
+    Custom: 'Custom',
+    Native: 'Native'
+} as const;
+
+// eslint-disable-next-line @typescript-eslint/no-redeclare
+export type SubtitleStylingOption = typeof SubtitleStylingOption[keyof typeof SubtitleStylingOption];
diff --git a/src/apps/stable/features/playback/utils/subtitleStyles.ts b/src/apps/stable/features/playback/utils/subtitleStyles.ts
new file mode 100644
index 0000000000..d247683470
--- /dev/null
+++ b/src/apps/stable/features/playback/utils/subtitleStyles.ts
@@ -0,0 +1,43 @@
+import { SubtitleStylingOption } from 'apps/stable/features/playback/constants/subtitleStylingOption';
+import browser from 'scripts/browser';
+import type { UserSettings } from 'scripts/settings/userSettings';
+
+// TODO: This type override should be removed when userSettings are properly typed
+interface SubtitleAppearanceSettings {
+    subtitleStyling: SubtitleStylingOption
+}
+
+export function useCustomSubtitles(userSettings: UserSettings) {
+    const subtitleAppearance = userSettings.getSubtitleAppearanceSettings() as SubtitleAppearanceSettings;
+    switch (subtitleAppearance.subtitleStyling) {
+        case SubtitleStylingOption.Native:
+            return false;
+        case SubtitleStylingOption.Custom:
+            return true;
+        default:
+            // after a system update, ps4 isn't showing anything when creating a track element dynamically
+            // going to have to do it ourselves
+            if (browser.ps4) {
+                return true;
+            }
+
+            // Tizen 5 doesn't support displaying secondary subtitles
+            if ((browser.tizenVersion && browser.tizenVersion >= 5) || browser.web0s) {
+                return true;
+            }
+
+            if (browser.edge) {
+                return true;
+            }
+
+            // font-size styling does not seem to work natively in firefox. Switching to custom subtitles element for firefox.
+            if (browser.firefox) {
+                return true;
+            }
+
+            // iOS/macOS global caption settings are causing huge font-size and margins
+            if (browser.safari) return true;
+
+            return false;
+    }
+}
diff --git a/src/elements/emby-scroller/Scroller.tsx b/src/elements/emby-scroller/Scroller.tsx
index baf054010a..3aa70e6ada 100644
--- a/src/elements/emby-scroller/Scroller.tsx
+++ b/src/elements/emby-scroller/Scroller.tsx
@@ -178,7 +178,6 @@ const Scroller: FC<PropsWithChildren<ScrollerProps>> = ({
             allowNativeScroll: !enableScrollButtons,
             forceHideScrollbars: enableScrollButtons,
             // In edge, with the native scroll, the content jumps around when hovering over the buttons
-            // @ts-expect-error browser doesn't explicitly declare browser.edge, so fails type checking
             requireAnimation: enableScrollButtons && browser.edge
         };
 
diff --git a/src/plugins/htmlVideoPlayer/plugin.js b/src/plugins/htmlVideoPlayer/plugin.js
index 34e3386270..0cb7bb419b 100644
--- a/src/plugins/htmlVideoPlayer/plugin.js
+++ b/src/plugins/htmlVideoPlayer/plugin.js
@@ -2,8 +2,11 @@ import DOMPurify from 'dompurify';
 import debounce from 'lodash-es/debounce';
 import Screenfull from 'screenfull';
 
+import { useCustomSubtitles } from 'apps/stable/features/playback/utils/subtitleStyles';
+import subtitleAppearanceHelper from 'components/subtitlesettings/subtitleappearancehelper';
 import { AppFeature } from 'constants/appFeature';
 import { ServerConnections } from 'lib/jellyfin-apiclient';
+import { currentSettings as userSettings } from 'scripts/settings/userSettings';
 import { MediaError } from 'types/mediaError';
 
 import browser from '../../scripts/browser';
@@ -330,8 +333,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     incrementFetchQueue() {
         if (this.#fetchQueue <= 0) {
             this.isFetching = true;
@@ -342,8 +345,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     decrementFetchQueue() {
         this.#fetchQueue--;
 
@@ -354,8 +357,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     updateVideoUrl(streamInfo) {
         const mediaSource = streamInfo.mediaSource;
         const item = streamInfo.item;
@@ -406,8 +409,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     setSrcWithFlvJs(elem, options, url) {
         return import('flv.js').then(({ default: flvjs }) => {
             const flvPlayer = flvjs.createPlayer({
@@ -432,8 +435,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     setSrcWithHlsJs(elem, options, url) {
         return new Promise((resolve, reject) => {
             requireHlsPlayer(async () => {
@@ -473,8 +476,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     async setCurrentSrc(elem, options) {
         elem.removeEventListener('error', this.onError);
 
@@ -577,8 +580,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     getTextTracks() {
         const videoElement = this.#mediaElement;
         if (videoElement) {
@@ -595,8 +598,8 @@ export class HtmlVideoPlayer {
     setSubtitleOffset = debounce(this._setSubtitleOffset, 100);
 
     /**
-         * @private
-         */
+     * @private
+     */
     _setSubtitleOffset(offset) {
         const offsetValue = parseFloat(offset);
 
@@ -624,8 +627,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     updateCurrentTrackOffset(offsetValue, currentTrackIndex = PRIMARY_TEXT_TRACK_INDEX) {
         let offsetToCompare = this.#currentTrackOffset;
         if (this.isSecondaryTrack(currentTrackIndex)) {
@@ -650,19 +653,19 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         * These browsers will not clear the existing active cue when setting an offset
-         * for native TextTracks.
-         * Any previous text tracks that are on the screen when the offset changes will remain next
-         * to the new tracks until they reach the end time of the new offset's instance of the track.
-         */
+     * @private
+     * These browsers will not clear the existing active cue when setting an offset
+     * for native TextTracks.
+     * Any previous text tracks that are on the screen when the offset changes will remain next
+     * to the new tracks until they reach the end time of the new offset's instance of the track.
+     */
     requiresHidingActiveCuesOnOffsetChange() {
         return !!browser.firefox;
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     hideTextTrackWithActiveCues(currentTrack) {
         if (currentTrack.activeCues) {
             currentTrack.mode = 'hidden';
@@ -670,11 +673,11 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * Forces the active cue to clear by disabling then re-enabling the track.
-         * The track mode is reverted inside of a 0ms timeout to free up the track
-         * and allow it to disable and clear the active cue.
-         * @private
-         */
+     * Forces the active cue to clear by disabling then re-enabling the track.
+     * The track mode is reverted inside of a 0ms timeout to free up the track
+     * and allow it to disable and clear the active cue.
+     * @private
+     */
     forceClearTextTrackActiveCues(currentTrack) {
         if (currentTrack.activeCues) {
             currentTrack.mode = 'disabled';
@@ -685,8 +688,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     setTextTrackSubtitleOffset(currentTrack, offsetValue, currentTrackIndex) {
         if (currentTrack.cues) {
             offsetValue = this.updateCurrentTrackOffset(offsetValue, currentTrackIndex);
@@ -712,8 +715,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     setTrackEventsSubtitleOffset(trackEvents, offsetValue, currentTrackIndex) {
         if (Array.isArray(trackEvents)) {
             offsetValue = this.updateCurrentTrackOffset(offsetValue, currentTrackIndex) * 1e7; // ticks
@@ -740,8 +743,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     isAudioStreamSupported(stream, deviceProfile, container) {
         const codec = (stream.Codec || '').toLowerCase();
 
@@ -764,8 +767,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     getSupportedAudioStreams() {
         const profile = this.#lastProfile;
 
@@ -807,8 +810,8 @@ export class HtmlVideoPlayer {
         // https://developer.mozilla.org/en-US/docs/Web/API/HTMLMediaElement/audioTracks
 
         /**
-             * @type {ArrayLike<any>|any[]}
-             */
+         * @type {ArrayLike<any>|any[]}
+         */
         const elemAudioTracks = elem.audioTracks || [];
         console.debug(`found ${elemAudioTracks.length} audio tracks`);
 
@@ -890,26 +893,26 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         * @param e {Event} The event received from the `<video>` element
-         */
+     * @private
+     * @param e {Event} The event received from the `<video>` element
+     */
     onEnded = (e) => {
         /**
-             * @type {HTMLMediaElement}
-             */
+         * @type {HTMLMediaElement}
+         */
         const elem = e.target;
         this.destroyCustomTrack(elem);
         onEndedInternal(this, elem, this.onError);
     };
 
     /**
-         * @private
-         * @param e {Event} The event received from the `<video>` element
-         */
+     * @private
+     * @param e {Event} The event received from the `<video>` element
+     */
     onTimeUpdate = (e) => {
         /**
-             * @type {HTMLMediaElement}
-             */
+         * @type {HTMLMediaElement}
+         */
         const elem = e.target;
         // get the player position and the transcoding offset
         const time = elem.currentTime;
@@ -933,21 +936,21 @@ export class HtmlVideoPlayer {
     };
 
     /**
-         * @private
-         * @param e {Event} The event received from the `<video>` element
-         */
+     * @private
+     * @param e {Event} The event received from the `<video>` element
+     */
     onVolumeChange = (e) => {
         /**
-             * @type {HTMLMediaElement}
-             */
+         * @type {HTMLMediaElement}
+         */
         const elem = e.target;
         saveVolume(elem.volume);
         Events.trigger(this, 'volumechange');
     };
 
     /**
-         * @private
-         */
+     * @private
+     */
     onNavigatedToOsd = () => {
         const dlg = this.#videoDialog;
         if (dlg) {
@@ -958,8 +961,8 @@ export class HtmlVideoPlayer {
     };
 
     /**
-         * @private
-         */
+     * @private
+     */
     onStartedAndNavigatedToOsd() {
         // If this causes a failure during navigation we end up in an awkward UI state
         this.setCurrentTrackElement(this.#subtitleTrackIndexToSetOnPlaying);
@@ -970,23 +973,23 @@ export class HtmlVideoPlayer {
 
         if (this.#secondarySubtitleTrackIndexToSetOnPlaying != null && this.#secondarySubtitleTrackIndexToSetOnPlaying >= 0) {
             /**
-                 * Using a 0ms timeout to set the secondary subtitles because of some weird race condition when
-                 * setting both primary and secondary tracks at the same time.
-                 * The `TextTrack` content and cues will somehow get mixed up and each track will play a mix of both languages.
-                 * Putting this in a timeout fixes it completely.
-                 */
+             * Using a 0ms timeout to set the secondary subtitles because of some weird race condition when
+             * setting both primary and secondary tracks at the same time.
+             * The `TextTrack` content and cues will somehow get mixed up and each track will play a mix of both languages.
+             * Putting this in a timeout fixes it completely.
+             */
             setTimeout(() => this.setSecondarySubtitleStreamIndex(this.#secondarySubtitleTrackIndexToSetOnPlaying), 0);
         }
     }
 
     /**
-         * @private
-         * @param e {Event} The event received from the `<video>` element
-         */
+     * @private
+     * @param e {Event} The event received from the `<video>` element
+     */
     onPlaying = (e) => {
         /**
-             * @type {HTMLMediaElement}
-             */
+         * @type {HTMLMediaElement}
+         */
         const elem = e.target;
         if (!this.#started) {
             this.#started = true;
@@ -1015,15 +1018,15 @@ export class HtmlVideoPlayer {
     };
 
     /**
-         * @private
-         */
+     * @private
+     */
     onPlay = () => {
         Events.trigger(this, 'unpause');
     };
 
     /**
-         * @private
-         */
+     * @private
+     */
     ensureValidVideo(elem) {
         if (elem !== this.#mediaElement) {
             return;
@@ -1041,22 +1044,22 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     onClick = () => {
         Events.trigger(this, 'click');
     };
 
     /**
-         * @private
-         */
+     * @private
+     */
     onDblClick = () => {
         Events.trigger(this, 'dblclick');
     };
 
     /**
-         * @private
-         */
+     * @private
+     */
     onPause = () => {
         Events.trigger(this, 'pause');
     };
@@ -1066,13 +1069,13 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         * @param e {Event} The event received from the `<video>` element
-         */
+     * @private
+     * @param e {Event} The event received from the `<video>` element
+     */
     onError = (e) => {
         /**
-             * @type {HTMLMediaElement}
-             */
+         * @type {HTMLMediaElement}
+         */
         const elem = e.target;
         const errorCode = elem.error ? (elem.error.code || 0) : 0;
         const errorMessage = elem.error ? (elem.error.message || '') : '';
@@ -1112,8 +1115,8 @@ export class HtmlVideoPlayer {
     };
 
     /**
-         * @private
-         */
+     * @private
+     */
     destroyCustomRenderedTrackElements(targetTrackIndex) {
         if (this.isPrimaryTrack(targetTrackIndex)) {
             if (this.#videoSubtitlesElem) {
@@ -1137,8 +1140,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     destroyNativeTracks(videoElement, targetTrackIndex) {
         if (videoElement) {
             const destroySingleTrack = typeof targetTrackIndex === 'number';
@@ -1157,8 +1160,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     destroyStoredTrackInfo(targetTrackIndex) {
         if (this.isPrimaryTrack(targetTrackIndex)) {
             this.#customTrackIndex = -1;
@@ -1175,8 +1178,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     destroyCustomTrack(videoElement, targetTrackIndex) {
         this.destroyCustomRenderedTrackElements(targetTrackIndex);
         this.destroyNativeTracks(videoElement, targetTrackIndex);
@@ -1196,8 +1199,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     fetchSubtitlesUwp(track) {
         return Windows.Storage.StorageFile.getFileFromPathAsync(track.Path).then(function (storageFile) {
             return Windows.Storage.FileIO.readTextAsync(storageFile);
@@ -1207,8 +1210,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     async fetchSubtitles(track, item) {
         if (window.Windows && itemHelper.isLocalItem(item)) {
             return this.fetchSubtitlesUwp(track, item);
@@ -1229,8 +1232,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     setTrackForDisplay(videoElement, track, targetTextTrackIndex = PRIMARY_TEXT_TRACK_INDEX) {
         if (!track) {
             // Destroy all tracks by passing undefined if there is no valid primary track
@@ -1262,8 +1265,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     renderSsaAss(videoElement, track, item) {
         const supportedFonts = ['application/vnd.ms-opentype', 'application/x-truetype-font', 'font/otf', 'font/ttf', 'font/woff', 'font/woff2'];
         const availableFonts = [];
@@ -1358,54 +1361,10 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
-    requiresCustomSubtitlesElement(userSettings) {
-        const subtitleAppearance = userSettings.getSubtitleAppearanceSettings();
-        switch (subtitleAppearance.subtitleStyling) {
-            case 'Native':
-                return false;
-            case 'Custom':
-                return true;
-            default:
-                // after a system update, ps4 isn't showing anything when creating a track element dynamically
-                // going to have to do it ourselves
-                if (browser.ps4) {
-                    return true;
-                }
-
-                // Tizen 5 doesn't support displaying secondary subtitles
-                if (browser.tizenVersion >= 5 || browser.web0s) {
-                    return true;
-                }
-
-                if (browser.edge) {
-                    return true;
-                }
-
-                // font-size styling does not seem to work natively in firefox. Switching to custom subtitles element for firefox.
-                if (browser.firefox) {
-                    return true;
-                }
-
-                if (browser.iOS) {
-                    const userAgent = navigator.userAgent.toLowerCase();
-                    // works in the browser but not the native app
-                    if ((userAgent.includes('os 9') || userAgent.includes('os 8')) && !userAgent.includes('safari')) {
-                        return true;
-                    }
-                }
-
-                return false;
-        }
-    }
-
-    /**
-         * @private
-         */
+     * @private
+     */
     renderSubtitlesWithCustomElement(videoElement, track, item, targetTextTrackIndex) {
-        Promise.all([import('../../scripts/settings/userSettings'), this.fetchSubtitles(track, item)]).then((results) => {
-            const [userSettings, subtitleData] = results;
+        this.fetchSubtitles(track, item).then((subtitleData) => {
             const subtitleAppearance = userSettings.getSubtitleAppearanceSettings();
             const subtitleVerticalPosition = parseInt(subtitleAppearance.verticalPosition, 10);
 
@@ -1441,20 +1400,18 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     setSubtitleAppearance(elem, innerElem) {
-        Promise.all([import('../../scripts/settings/userSettings'), import('../../components/subtitlesettings/subtitleappearancehelper')]).then(([userSettings, subtitleAppearanceHelper]) => {
-            subtitleAppearanceHelper.applyStyles({
-                text: innerElem,
-                window: elem
-            }, userSettings.getSubtitleAppearanceSettings());
-        });
+        subtitleAppearanceHelper.applyStyles({
+            text: innerElem,
+            window: elem
+        }, userSettings.getSubtitleAppearanceSettings());
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     getCueCss(appearance, selector) {
         return `${selector}::cue {
                 ${appearance.text.map((s) => s.value !== undefined && s.value !== '' ? `${s.name}:${s.value}!important;` : '').join('')}
@@ -1462,29 +1419,25 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     setCueAppearance() {
-        Promise.all([import('../../scripts/settings/userSettings'), import('../../components/subtitlesettings/subtitleappearancehelper')]).then(([userSettings, subtitleAppearanceHelper]) => {
-            const elementId = `${this.id}-cuestyle`;
+        const elementId = `${this.id}-cuestyle`;
 
-            let styleElem = document.querySelector(`#${elementId}`);
-            if (!styleElem) {
-                styleElem = document.createElement('style');
-                styleElem.id = elementId;
-                document.getElementsByTagName('head')[0].appendChild(styleElem);
-            }
+        let styleElem = document.querySelector(`#${elementId}`);
+        if (!styleElem) {
+            styleElem = document.createElement('style');
+            styleElem.id = elementId;
+            document.getElementsByTagName('head')[0].appendChild(styleElem);
+        }
 
-            styleElem.innerHTML = this.getCueCss(subtitleAppearanceHelper.getStyles(userSettings.getSubtitleAppearanceSettings()), '.htmlvideoplayer');
-        });
+        styleElem.innerHTML = this.getCueCss(subtitleAppearanceHelper.getStyles(userSettings.getSubtitleAppearanceSettings()), '.htmlvideoplayer');
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     async renderTracksEvents(videoElement, track, item, targetTextTrackIndex = PRIMARY_TEXT_TRACK_INDEX) {
-        const { currentSettings: userSettings } = await import('../../scripts/settings/userSettings');
-
         if (!itemHelper.isLocalItem(item) || track.IsExternal) {
             const format = (track.Codec || '').toLowerCase();
             if (format === 'ssa' || format === 'ass') {
@@ -1496,7 +1449,7 @@ export class HtmlVideoPlayer {
                 return;
             }
 
-            if (this.requiresCustomSubtitlesElement(userSettings)) {
+            if (useCustomSubtitles(userSettings)) {
                 this.renderSubtitlesWithCustomElement(videoElement, track, item, targetTextTrackIndex);
                 return;
             }
@@ -1555,8 +1508,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     updateSubtitleText(timeMs) {
         const allTrackEvents = [this.#currentTrackEvents, this.#currentSecondaryTrackEvents];
         const subtitleTextElements = [this.#videoSubtitlesElem, this.#videoSecondarySubtitlesElem];
@@ -1587,8 +1540,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     setCurrentTrackElement(streamIndex, targetTextTrackIndex) {
         console.debug(`setting new text track index to: ${streamIndex}`);
 
@@ -1648,8 +1601,8 @@ export class HtmlVideoPlayer {
     }
 
     /**
-         * @private
-         */
+     * @private
+     */
     createMediaElement(options) {
         const dlg = document.querySelector('.videoPlayerContainer');
 
diff --git a/src/scripts/browser.d.ts b/src/scripts/browser.d.ts
new file mode 100644
index 0000000000..0f8a5dfaf7
--- /dev/null
+++ b/src/scripts/browser.d.ts
@@ -0,0 +1,45 @@
+export default browser;
+/**
+ * Browser detection utility.
+ */
+declare namespace browser {
+    import version = version;
+    export { version };
+    import versionMajor = versionMajor;
+    export { versionMajor };
+    export let edge: boolean;
+    export let edgeChromium: boolean;
+    export let firefox: boolean;
+    export let safari: boolean;
+    export let osx: boolean;
+    export let ipad: boolean;
+    export let ps4: boolean;
+    export let tv: boolean;
+    export let mobile: boolean;
+    export let xboxOne: boolean;
+    export let animate: boolean;
+    export let hisense: boolean;
+    export let tizen: boolean;
+    export let vidaa: boolean;
+    export let web0s: boolean;
+    export let edgeUwp: boolean;
+    export let web0sVersion: number | undefined;
+    export let tizenVersion: number | undefined;
+    export let orsay: boolean;
+    export let operaTv: boolean;
+    export let slow: boolean;
+    export let touch: boolean;
+    export let keyboard: boolean;
+    export { supportsCssAnimation };
+    export let iOS: boolean;
+    export let iOSVersion: number | undefined;
+}
+
+declare namespace matched {
+    export { browser };
+    export { version };
+    export let platform: string;
+    export { versionMajor };
+}
+
+declare function supportsCssAnimation(allowPrefix: any): any;
diff --git a/src/scripts/settings/userSettings.js b/src/scripts/settings/userSettings.js
index 30904ac51a..439c1df87a 100644
--- a/src/scripts/settings/userSettings.js
+++ b/src/scripts/settings/userSettings.js
@@ -600,7 +600,7 @@ export class UserSettings {
 
     /**
      * Get subtitle appearance settings.
-     * @param {string|undefined} key - Settings key.
+     * @param {string|undefined} [key] - Settings key.
      * @return {Object} Subtitle appearance settings.
      */
     getSubtitleAppearanceSettings(key) {