diff --git a/ext/css/settings.css b/ext/css/settings.css
index c0e75fc2..6bc377c2 100644
--- a/ext/css/settings.css
+++ b/ext/css/settings.css
@@ -134,7 +134,7 @@ ul+p,
 ul+ol,
 ul+ul,
 li {
-    margin: 0.425em 0;
+    margin: 0.425em 0 0;
 }
 a {
     color: var(--link-color);
@@ -2152,6 +2152,13 @@ button.hotkey-list-item-enabled-button[data-scope-count='0'] {
     margin-left: 0.375em;
 }
 
+.page-loading-stalled-notification {
+    border: 1px solid var(--danger-color);
+}
+:root:not([data-loading-stalled=true]) .page-loading-stalled-notification {
+    display: none;
+}
+
 
 /* Generic layouts */
 .margin-above {
@@ -2233,19 +2240,25 @@ button.hotkey-list-item-enabled-button[data-scope-count='0'] {
 
 
 /* Environment-specific display */
+:root[data-browser=unknown] [data-show-for-browser],
+:root[data-browser=unknown] [data-hide-for-browser],
 :root[data-browser=edge] [data-show-for-browser]:not([data-show-for-browser~=edge]),
 :root[data-browser=edge-legacy] [data-show-for-browser]:not([data-show-for-browser~=edge-legacy]),
 :root[data-browser=chrome] [data-show-for-browser]:not([data-show-for-browser~=chrome]),
+:root[data-browser=safari] [data-show-for-browser]:not([data-show-for-browser~=safari]),
 :root[data-browser=firefox] [data-show-for-browser]:not([data-show-for-browser~=firefox]),
 :root[data-browser=firefox-mobile] [data-show-for-browser]:not([data-show-for-browser~=firefox-mobile]),
 :root[data-browser=edge] [data-hide-for-browser~=edge],
 :root[data-browser=edge-legacy] [data-hide-for-browser~=edge-legacy],
 :root[data-browser=chrome] [data-hide-for-browser~=chrome],
+:root[data-browser=safari] [data-hide-for-browser~=safari],
 :root[data-browser=firefox] [data-hide-for-browser~=firefox],
 :root[data-browser=firefox-mobile] [data-hide-for-browser~=firefox-mobile] {
     display: none;
 }
 
+:root[data-os=unknown] [data-show-for-os],
+:root[data-os=unknown] [data-hide-for-os],
 :root[data-os=mac] [data-show-for-os]:not([data-show-for-os~=mac]),
 :root[data-os=win] [data-show-for-os]:not([data-show-for-os~=win]),
 :root[data-os=android] [data-show-for-os]:not([data-show-for-os~=android]),
@@ -2261,6 +2274,8 @@ button.hotkey-list-item-enabled-button[data-scope-count='0'] {
     display: none;
 }
 
+:root[data-manifest-version=unknown] [data-show-for-manifest-version],
+:root[data-manifest-version=unknown] [data-hide-for-manifest-version],
 :root[data-manifest-version='2'] [data-show-for-manifest-version]:not([data-show-for-manifest-version~='2']),
 :root[data-manifest-version='3'] [data-show-for-manifest-version]:not([data-show-for-manifest-version~='3']),
 :root[data-manifest-version='2'] [data-hide-for-manifest-version~='2'],
diff --git a/ext/js/background/backend.js b/ext/js/background/backend.js
index a6b9c0dc..21b18e99 100644
--- a/ext/js/background/backend.js
+++ b/ext/js/background/backend.js
@@ -112,7 +112,7 @@ class Backend {
             ['getDisplayTemplatesHtml',      {async: true,  contentScript: true,  handler: this._onApiGetDisplayTemplatesHtml.bind(this)}],
             ['getZoom',                      {async: true,  contentScript: true,  handler: this._onApiGetZoom.bind(this)}],
             ['getDefaultAnkiFieldTemplates', {async: false, contentScript: true,  handler: this._onApiGetDefaultAnkiFieldTemplates.bind(this)}],
-            ['getDictionaryInfo',            {async: true,  contentScript: false, handler: this._onApiGetDictionaryInfo.bind(this)}],
+            ['getDictionaryInfo',            {async: true,  contentScript: true,  handler: this._onApiGetDictionaryInfo.bind(this)}],
             ['getDictionaryCounts',          {async: true,  contentScript: false, handler: this._onApiGetDictionaryCounts.bind(this)}],
             ['purgeDatabase',                {async: true,  contentScript: false, handler: this._onApiPurgeDatabase.bind(this)}],
             ['getMedia',                     {async: true,  contentScript: true,  handler: this._onApiGetMedia.bind(this)}],
@@ -1288,10 +1288,14 @@ class Backend {
     }
 
     _validatePrivilegedMessageSender(sender) {
-        const url = sender.url;
-        if (!(typeof url === 'string' && yomichan.isExtensionUrl(url))) {
-            throw new Error('Invalid message sender');
+        let {url} = sender;
+        if (typeof url === 'string' && yomichan.isExtensionUrl(url)) { return; }
+        const {tab} = url;
+        if (typeof tab === 'object' && tab !== null) {
+            ({url} = tab);
+            if (typeof url === 'string' && yomichan.isExtensionUrl(url)) { return; }
         }
+        throw new Error('Invalid message sender');
     }
 
     _getBrowserIconTitle() {
diff --git a/ext/js/background/environment.js b/ext/js/background/environment.js
index 04099ca1..8111741f 100644
--- a/ext/js/background/environment.js
+++ b/ext/js/background/environment.js
@@ -83,9 +83,23 @@ class Environment {
             } catch (e) {
                 // NOP
             }
+            if (this._isSafari()) {
+                return 'safari';
+            }
             return 'firefox';
         } else {
             return 'chrome';
         }
     }
+
+    _isSafari() {
+        const {vendor, userAgent} = navigator;
+        return (
+            typeof vendor === 'string' &&
+            typeof userAgent === 'string' &&
+            vendor.includes('Apple') &&
+            !userAgent.includes('CriOS') &&
+            !userAgent.includes('FxiOS')
+        );
+    }
 }
diff --git a/ext/js/media/audio-system.js b/ext/js/media/audio-system.js
index cf63511f..cc2bcfc0 100644
--- a/ext/js/media/audio-system.js
+++ b/ext/js/media/audio-system.js
@@ -19,18 +19,20 @@
  * TextToSpeechAudio
  */
 
-class AudioSystem {
+class AudioSystem extends EventDispatcher {
     constructor() {
+        super();
         this._fallbackAudio = null;
     }
 
     prepare() {
         // speechSynthesis.getVoices() will not be populated unless some API call is made.
-        if (typeof speechSynthesis === 'undefined') { return; }
-
-        const eventListeners = new EventListenerCollection();
-        const onVoicesChanged = () => { eventListeners.removeAllEventListeners(); };
-        eventListeners.addEventListener(speechSynthesis, 'voiceschanged', onVoicesChanged, false);
+        if (
+            typeof speechSynthesis !== 'undefined' &&
+            typeof speechSynthesis.addEventListener === 'function'
+        ) {
+            speechSynthesis.addEventListener('voiceschanged', this._onVoicesChanged.bind(this), false);
+        }
     }
 
     getFallbackAudio() {
@@ -64,6 +66,10 @@ class AudioSystem {
 
     // Private
 
+    _onVoicesChanged(e) {
+        this.trigger('voiceschanged', e);
+    }
+
     _isAudioValid(audio, source) {
         switch (source) {
             case 'jpod101':
diff --git a/ext/js/pages/action-popup-main.js b/ext/js/pages/action-popup-main.js
index 2de986da..4934802b 100644
--- a/ext/js/pages/action-popup-main.js
+++ b/ext/js/pages/action-popup-main.js
@@ -103,6 +103,10 @@ class DisplayController {
                     let tab;
                     try {
                         tab = await this._getCurrentTab();
+                        // Safari assigns a tab object to the popup, other browsers do not
+                        if (tab && await this._isSafari()) {
+                            tab = void 0;
+                        }
                     } catch (e) {
                         // NOP
                     }
@@ -220,6 +224,11 @@ class DisplayController {
             node.hidden = false;
         }
     }
+
+    async _isSafari() {
+        const {browser} = await yomichan.api.getEnvironmentInfo();
+        return browser === 'safari';
+    }
 }
 
 (async () => {
diff --git a/ext/js/pages/settings/audio-controller.js b/ext/js/pages/settings/audio-controller.js
index e62383a8..6b1ce0b5 100644
--- a/ext/js/pages/settings/audio-controller.js
+++ b/ext/js/pages/settings/audio-controller.js
@@ -39,9 +39,7 @@ class AudioController {
 
         this._audioSourceAddButton.addEventListener('click', this._onAddAudioSource.bind(this), false);
 
-        if (typeof speechSynthesis !== 'undefined') {
-            speechSynthesis.addEventListener('voiceschanged', this._updateTextToSpeechVoices.bind(this), false);
-        }
+        this._audioSystem.on('voiceschanged', this._updateTextToSpeechVoices.bind(this), false);
         this._updateTextToSpeechVoices();
 
         document.querySelector('#text-to-speech-voice-test').addEventListener('click', this._onTestTextToSpeech.bind(this), false);
diff --git a/ext/js/pages/settings/settings-main.js b/ext/js/pages/settings/settings-main.js
index 2560685c..6f3e2a58 100644
--- a/ext/js/pages/settings/settings-main.js
+++ b/ext/js/pages/settings/settings-main.js
@@ -24,6 +24,7 @@
  * DictionaryController
  * DictionaryImportController
  * DocumentFocusController
+ * Environment
  * ExtensionKeyboardShortcutController
  * GenericSettingController
  * KeyboardShortcutController
@@ -47,11 +48,16 @@
  */
 
 async function setupEnvironmentInfo() {
+    const {dataset} = document.documentElement;
     const {manifest_version: manifestVersion} = chrome.runtime.getManifest();
-    const {browser, platform} = await yomichan.api.getEnvironmentInfo();
-    document.documentElement.dataset.browser = browser;
-    document.documentElement.dataset.os = platform.os;
-    document.documentElement.dataset.manifestVersion = `${manifestVersion}`;
+    dataset.manifestVersion = `${manifestVersion}`;
+
+    const environment = new Environment();
+    await environment.prepare();
+    const {browser, platform} = environment.getInfo();
+
+    dataset.browser = browser;
+    dataset.os = platform.os;
 }
 
 async function setupGenericSettingsController(genericSettingController) {
@@ -67,9 +73,20 @@ async function setupGenericSettingsController(genericSettingController) {
         const statusFooter = new StatusFooter(document.querySelector('.status-footer-container'));
         statusFooter.prepare();
 
+        setupEnvironmentInfo();
+
+        let prepareTimer = setTimeout(() => {
+            prepareTimer = null;
+            document.documentElement.dataset.loadingStalled = 'true';
+        }, 1000);
+
         await yomichan.prepare();
 
-        setupEnvironmentInfo();
+        if (prepareTimer !== null) {
+            clearTimeout(prepareTimer);
+            prepareTimer = null;
+        }
+        delete document.documentElement.dataset.loadingStalled;
 
         const optionsFull = await yomichan.api.optionsGetFull();
 
diff --git a/ext/settings.html b/ext/settings.html
index d629e6a6..732a96e2 100644
--- a/ext/settings.html
+++ b/ext/settings.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html lang="en">
+<html lang="en" data-browser="unknown" data-os="unknown" data-manifest-version="unknown">
 <head>
     <meta charset="UTF-8">
     <meta name="viewport" content="width=device-width,initial-scale=1">
@@ -59,6 +59,23 @@
 
     <h1>Yomichan Settings</h1>
 
+    <!-- Notifications -->
+    <div class="settings-group settings-group-top-margin page-loading-stalled-notification">
+        <div class="settings-item"><div class="settings-item-inner settings-item-inner-wrappable">
+            <div class="settings-item-left">
+                <div class="settings-item-label">
+                    <p>
+                        This page is taking longer than expected to load.
+                    </p>
+                    <p data-show-for-browser="safari">
+                        Due to a bug in Safari, it may be necessary to click the <img src="/images/yomichan-icon.svg" class="inline-icon" alt=""> <em>Yomichan</em>
+                        button in the browser bar to fully load the page
+                    </p>
+                </div>
+            </div>
+        </div></div>
+    </div>
+
     <!-- Profile -->
     <div class="heading-container">
         <div class="heading-container-icon"><span class="icon" data-icon="profile"></span></div>