diff --git a/language/en/webpushnotifications_module_ucp.php b/language/en/webpushnotifications_module_ucp.php
index be503ca..8a481e3 100644
--- a/language/en/webpushnotifications_module_ucp.php
+++ b/language/en/webpushnotifications_module_ucp.php
@@ -48,7 +48,7 @@
 	'NOTIFY_WEBPUSH_UNSUBSCRIBE'	=> 'Disable to unsubscribe',
 	'NOTIFY_WEBPUSH_DROPDOWN_TITLE'	=> 'Visit notifications settings to set your preferred push notifications.',
 	'NOTIFY_WEBPUSH_DENIED'			=> 'You have denied notifications from this site. To enable push notifications, allow notifications from this site in your browser settings.',
-	'NOTIFY_WEBPUSH_DISABLED'		=> 'Push notifications not supported',
+	'NOTIFY_WEBPUSH_NOT_SUPPORTED'	=> 'Push notifications not supported',
 	'NOTIFY_WEBPUSH_POPUP_TITLE'	=> 'Allow browser notifications?',
 	'NOTIFY_WEBPUSH_POPUP_MESSAGE'	=> 'We would like to send you browser notifications for replies, private messages, and relevant forum activity. Optional — you can manage these settings at any time.',
 	'NOTIFY_WEBPUSH_POPUP_ALLOW'	=> 'Allow',
diff --git a/language/ru/webpushnotifications_module_ucp.php b/language/ru/webpushnotifications_module_ucp.php
index 10b5e7a..c670739 100644
--- a/language/ru/webpushnotifications_module_ucp.php
+++ b/language/ru/webpushnotifications_module_ucp.php
@@ -48,7 +48,7 @@
 	'NOTIFY_WEBPUSH_UNSUBSCRIBE'	=> 'Отписаться',
 	'NOTIFY_WEBPUSH_DROPDOWN_TITLE'	=> 'Посетите настройки уведомлений, чтобы установить предпочтительные типы браузерных уведомлений.',
 	'NOTIFY_WEBPUSH_DENIED'			=> 'Вы запретили браузерные уведомления для даного сайта. Для того, чтобы подписаться, необходимо их разрешить в настройках браузера.',
-	'NOTIFY_WEBPUSH_DISABLED'		=> 'Не поддерживается',
+	'NOTIFY_WEBPUSH_NOT_SUPPORTED'	=> 'Не поддерживается',
 	'NOTIFY_WEBPUSH_POPUP_TITLE'	=> 'Включить браузерные уведомления?',
 	'NOTIFY_WEBPUSH_POPUP_MESSAGE'	=> 'Браузерные уведомления позволяют быстро получать информацию о новых ответах, личных сообщениях и других активностях на данной конференции.  Функцию можно отключить или включить в любое время в настройках уведомлений в Личном разделе.',
 	'NOTIFY_WEBPUSH_POPUP_ALLOW'	=> 'Включить',
diff --git a/styles/all/template/event/notification_dropdown_footer_after.html b/styles/all/template/event/notification_dropdown_footer_after.html
index 8f5c54a..defa510 100644
--- a/styles/all/template/event/notification_dropdown_footer_after.html
+++ b/styles/all/template/event/notification_dropdown_footer_after.html
@@ -1,7 +1,7 @@
 {% if NOTIFICATIONS_WEBPUSH_ENABLE and notification_types is not defined %}
 	<div class="wpn-notification-dropdown-footer" title="{{ lang('NOTIFY_WEBPUSH_DROPDOWN_TITLE') }}">
 		<span class="ellipsis-text">{{ lang('NOTIFY_WEBPUSH_ENABLE_SLIDER') ~ lang('COLON') }}</span>
-		<button id="subscribe_webpush" name="subscribe_webpush" data-l-err="{{ lang('INFORMATION') }}" data-l-msg="{{ lang('NOTIFY_WEBPUSH_DENIED') }}">
+		<button id="subscribe_webpush" name="subscribe_webpush" data-l-err="{{ lang('INFORMATION')|e('html_attr') }}" data-l-msg="{{ lang('NOTIFY_WEBPUSH_DENIED')|e('html_attr') }}" data-l-unsupported="{{ lang('NOTIFY_WEBPUSH_NOT_SUPPORTED')|e('html_attr') }}">
 			<i class="icon fa-toggle-off fa-fw icon-lightgray" aria-hidden="true" title="{{ lang('NOTIFY_WEBPUSH_SUBSCRIBE') }}"><span class="sr-only">{{ lang('NOTIFY_WEBPUSH_SUBSCRIBE') }}</span></i>
 		</button>
 		<button id="unsubscribe_webpush" name="unsubscribe_webpush" class="hidden">
diff --git a/styles/all/template/ucp_notifications_webpush.html b/styles/all/template/ucp_notifications_webpush.html
index 16ebf96..35a0298 100644
--- a/styles/all/template/ucp_notifications_webpush.html
+++ b/styles/all/template/ucp_notifications_webpush.html
@@ -3,7 +3,7 @@
 		serviceWorkerUrl: '{{ U_WEBPUSH_WORKER_URL }}',
 		subscribeUrl: '{{ U_WEBPUSH_SUBSCRIBE }}',
 		unsubscribeUrl: '{{ U_WEBPUSH_UNSUBSCRIBE }}',
-		ajaxErrorTitle: '{{ lang('AJAX_ERROR_TITLE') }}',
+		ajaxErrorTitle: '{{ lang_js('AJAX_ERROR_TITLE') }}',
 		vapidPublicKey: '{{ VAPID_PUBLIC_KEY }}',
 		formTokens: {
 			creationTime: '{{ WEBPUSH_FORM_TOKENS.creation_time }}',
diff --git a/styles/all/template/webpush.js b/styles/all/template/webpush.js
index e57b5d3..3481bb9 100644
--- a/styles/all/template/webpush.js
+++ b/styles/all/template/webpush.js
@@ -90,7 +90,7 @@ function PhpbbWebpush() {
 		}
 
 		if (subscribeButton.type === 'submit' || subscribeButton.classList.contains('button')) {
-			subscribeButton.value = subscribeButton.getAttribute('data-disabled-msg');
+			subscribeButton.value = subscribeButton.getAttribute('data-l-unsupported');
 		}
 	}
 
@@ -164,8 +164,8 @@ function PhpbbWebpush() {
 			allowBtn.addEventListener('click', (event) => {
 				event.stopPropagation();
 				popup.style.display = 'none';
-				subscribeButtonHandler({
-					preventDefault: () => {}
+				subscribeButtonHandler(event).catch(error => {
+					console.error('Subscription handler error:', error);
 				});
 			});
 		}
@@ -237,48 +237,60 @@ function PhpbbWebpush() {
 	async function subscribeButtonHandler(event) {
 		event.preventDefault();
 
-		subscribeButton.addEventListener('click', subscribeButtonHandler);
+		subscribeButton.removeEventListener('click', subscribeButtonHandler);
 
-		// Prevent the user from clicking the subscribe button multiple times.
-		const result = await Notification.requestPermission();
-		if (result === 'denied') {
-			phpbb.alert(subscribeButton.getAttribute('data-l-err'), subscribeButton.getAttribute('data-l-msg'));
-			return;
-		}
+		try {
+			// Prevent the user from clicking the subscribe button multiple times.
+			const result = await Notification.requestPermission();
+			if (result === 'denied') {
+				phpbb.alert(subscribeButton.getAttribute('data-l-err'), subscribeButton.getAttribute('data-l-msg'));
+				return;
+			}
 
-		const registration = await navigator.serviceWorker.getRegistration(serviceWorkerUrl);
+			const registration = await navigator.serviceWorker.getRegistration(serviceWorkerUrl);
 
-		// We might already have a subscription that is unknown to this instance of phpBB.
-		// Unsubscribe before trying to subscribe again.
-		if (typeof registration !== 'undefined') {
-			const subscribed = await registration.pushManager.getSubscription();
-			if (subscribed) {
-				await subscribed.unsubscribe();
+			// We might already have a subscription that is unknown to this instance of phpBB.
+			// Unsubscribe before trying to subscribe again.
+			if (typeof registration !== 'undefined') {
+				const subscribed = await registration.pushManager.getSubscription();
+				if (subscribed) {
+					await subscribed.unsubscribe();
+				}
 			}
-		}
 
-		const newSubscription = await registration.pushManager.subscribe({
-			userVisibleOnly: true,
-			applicationServerKey: urlB64ToUint8Array(vapidPublicKey),
-		});
+			const newSubscription = await registration.pushManager.subscribe({
+				userVisibleOnly: true,
+				applicationServerKey: urlB64ToUint8Array(vapidPublicKey),
+			});
 
-		const loadingIndicator = phpbb.loadingIndicator();
-		fetch(subscribeUrl, {
-			method: 'POST',
-			headers: {
-				'X-Requested-With': 'XMLHttpRequest',
-			},
-			body: getFormData(newSubscription),
-		})
-			.then(response => {
-				loadingIndicator.fadeOut(phpbb.alertTime);
-				return response.json();
+			const loadingIndicator = phpbb.loadingIndicator();
+			fetch(subscribeUrl, {
+				method: 'POST',
+				headers: {
+					'X-Requested-With': 'XMLHttpRequest',
+				},
+				body: getFormData(newSubscription),
 			})
-			.then(handleSubscribe)
-			.catch(error => {
-				loadingIndicator.fadeOut(phpbb.alertTime);
-				phpbb.alert(ajaxErrorTitle, error);
-			});
+				.then(response => {
+					loadingIndicator.fadeOut(phpbb.alertTime);
+					return response.json();
+				})
+				.then(handleSubscribe)
+				.catch(error => {
+					loadingIndicator.fadeOut(phpbb.alertTime);
+					phpbb.alert(ajaxErrorTitle, error);
+				});
+		} catch (error) {
+			promptDenied.set(); // deny the prompt on error to prevent repeated prompting
+			const popup = document.getElementById('wpn_popup_prompt');
+			if (popup) {
+				popup.style.display = 'none';
+			}
+			console.error('Push subscription error:', error);
+			phpbb.alert(subscribeButton.getAttribute('data-l-err'), error.message || subscribeButton.getAttribute('data-l-unsupported'));
+		} finally {
+			subscribeButton.addEventListener('click', subscribeButtonHandler);
+		}
 	}
 
 	/**
diff --git a/styles/prosilver/template/event/ucp_notifications_content_before.html b/styles/prosilver/template/event/ucp_notifications_content_before.html
index 3ea0100..11be3b0 100644
--- a/styles/prosilver/template/event/ucp_notifications_content_before.html
+++ b/styles/prosilver/template/event/ucp_notifications_content_before.html
@@ -5,7 +5,7 @@
 				<dl>
 					<dt><label for="subscribe_webpush">{{ lang('NOTIFY_WEBPUSH_NOTIFICATIONS') ~ lang('COLON') }}</label></dt>
 					<dd>
-						<input id="subscribe_webpush" type="submit" name="subscribe_webpush" value="{{ lang('NOTIFY_WEBPUSH_ENABLE') }}" class="wpn button1 button button-form" data-l-err="{{ lang('INFORMATION') }}" data-l-msg="{{ lang('NOTIFY_WEBPUSH_DENIED') }}" data-disabled-msg="{{ lang('NOTIFY_WEBPUSH_DISABLED') }}">
+						<input id="subscribe_webpush" type="submit" name="subscribe_webpush" value="{{ lang('NOTIFY_WEBPUSH_ENABLE') }}" class="wpn button1 button button-form" data-l-err="{{ lang('INFORMATION')|e('html_attr') }}" data-l-msg="{{ lang('NOTIFY_WEBPUSH_DENIED')|e('html_attr') }}" data-l-unsupported="{{ lang('NOTIFY_WEBPUSH_NOT_SUPPORTED')|e('html_attr') }}">
 						<input id="unsubscribe_webpush" type="submit" name="unsubscribe_webpush" value="{{ lang('NOTIFY_WEBPUSH_DISABLE') }}" class="wpn button1 button button-form hidden">
 						<br><span>{{ lang('NOTIFY_WEBPUSH_ENABLE_EXPLAIN') }}</span>
 					</dd>