diff --git a/acp/wpn_acp_module.php b/acp/wpn_acp_module.php
index 30c3e5f..88131ab 100644
--- a/acp/wpn_acp_module.php
+++ b/acp/wpn_acp_module.php
@@ -379,7 +379,7 @@ protected function get_styles(): array
 			FROM ' . STYLES_TABLE . '
 			WHERE style_active = 1
 			ORDER BY style_name';
-		$result = $this->db->sql_query($sql, 3600);
+		$result = $this->db->sql_query($sql);
 
 		$rows = $this->db->sql_fetchrowset($result);
 		$this->db->sql_freeresult($result);
diff --git a/adm/style/wpn_acp_pwa.html b/adm/style/wpn_acp_pwa.html
index d0b6391..d9b74a4 100644
--- a/adm/style/wpn_acp_pwa.html
+++ b/adm/style/wpn_acp_pwa.html
@@ -53,11 +53,11 @@ <h1>{{ lang('PWA_THEME_COLOURS') }}</h1>
 				<dt><label for="pwa_theme_color_{{ style.style_id }}">{{ style.style_name ~ lang('COLON') }}</label></dt>
 				<dd>
 					<span class="color-pickers">
-						<input type="text" id="pwa_theme_color_{{ style.style_id }}" name="pwa_theme_color_{{ style.style_id }}" size="8" value="{{ style.pwa_theme_color }}" placeholder="{{ constant('phpbb\\webpushnotifications\\ext::PWA_THEME_COLOR') }}">
+						<input type="text" id="pwa_theme_color_{{ style.style_id }}" name="pwa_theme_color_{{ style.style_id }}" size="8" value="{{ style.pwa_theme_color }}" placeholder="#000000">
 						<input type="color" id="pwa_theme_color_picker_{{ style.style_id }}" aria-label="{{ lang('PWA_THEME_COLOUR') }}" value="{{ style.pwa_theme_color|default(default_color) }}">
 					</span>
 					<span class="color-pickers">
-						<input type="text" id="pwa_bg_color_{{ style.style_id }}" name="pwa_bg_color_{{ style.style_id }}" size="8" value="{{ style.pwa_bg_color }}" placeholder="{{ constant('phpbb\\webpushnotifications\\ext::PWA_BG_COLOR') }}">
+						<input type="text" id="pwa_bg_color_{{ style.style_id }}" name="pwa_bg_color_{{ style.style_id }}" size="8" value="{{ style.pwa_bg_color }}" placeholder="#ffffff">
 						<input type="color" id="pwa_bg_color_picker_{{ style.style_id }}" aria-label="{{ lang('PWA_BACKGROUND_COLOUR') }}" value="{{ style.pwa_bg_color|default(default_color) }}">
 					</span>
 				</dd>
diff --git a/controller/manifest.php b/controller/manifest.php
index a1b71ba..19649dd 100644
--- a/controller/manifest.php
+++ b/controller/manifest.php
@@ -61,10 +61,18 @@ public function handle(): JsonResponse
 			'orientation'	=> 'portrait',
 			'start_url'		=> $start_url,
 			'scope'			=> $scope,
-			'theme_color'	=> !empty($this->user->style['pwa_theme_color']) ? $this->user->style['pwa_theme_color'] : ext::PWA_THEME_COLOR,
-			'background_color' => !empty($this->user->style['pwa_bg_color']) ? $this->user->style['pwa_bg_color'] : ext::PWA_BG_COLOR,
 		];
 
+		if (!empty($this->user->style['pwa_theme_color']))
+		{
+			$manifest['theme_color'] = $this->user->style['pwa_theme_color'];
+		}
+
+		if (!empty($this->user->style['pwa_bg_color']))
+		{
+			$manifest['background_color'] = $this->user->style['pwa_bg_color'];
+		}
+
 		if (!empty($this->config['pwa_icon_small']) && !empty($this->config['pwa_icon_large']))
 		{
 			$manifest['icons'] = [
diff --git a/event/listener.php b/event/listener.php
index 4e5ae34..3e882d2 100644
--- a/event/listener.php
+++ b/event/listener.php
@@ -155,8 +155,8 @@ public function pwa_manifest()
 			'U_MANIFEST_URL'	=> $this->controller_helper->route('phpbb_webpushnotifications_manifest_controller'),
 			'U_TOUCH_ICON'		=> $this->config['pwa_icon_small'] ? ext::PWA_ICON_DIR . '/' . $this->config['pwa_icon_small'] : null,
 			'SHORT_SITE_NAME'	=> $this->config['pwa_short_name'] ?: $this->trim_shortname($this->config['sitename']),
-			'PWA_THEME_COLOR'	=> !empty($this->user->style['pwa_theme_color']) ? $this->user->style['pwa_theme_color'] : ext::PWA_THEME_COLOR,
-			'PWA_BG_COLOR'		=> !empty($this->user->style['pwa_bg_color']) ? $this->user->style['pwa_bg_color'] : ext::PWA_BG_COLOR,
+			'PWA_THEME_COLOR'	=> $this->user->style['pwa_theme_color'] ?? '',
+			'PWA_BG_COLOR'		=> $this->user->style['pwa_bg_color'] ?? '',
 			'S_PWA_SHOW_BANNER'	=> !empty($this->config['pwa_show_install_banner']) && $this->is_mobile_phone(),
 		]);
 	}
diff --git a/ext.php b/ext.php
index e58af68..56f2872 100644
--- a/ext.php
+++ b/ext.php
@@ -20,12 +20,6 @@ class ext extends \phpbb\extension\base
 	 */
 	public const PWA_ICON_DIR = 'images/site_icons';
 
-	/** @var string PWA theme color */
-	public const PWA_THEME_COLOR = '#000000';
-
-	/** @var string PWA background color */
-	public const PWA_BG_COLOR = '#ffffff';
-
 	/**
 	 * Require phpBB 3.3.12 due to new template and core events.
 	 */
diff --git a/styles/all/template/event/overall_header_head_append.html b/styles/all/template/event/overall_header_head_append.html
index e29b1bb..2fc12ad 100644
--- a/styles/all/template/event/overall_header_head_append.html
+++ b/styles/all/template/event/overall_header_head_append.html
@@ -1,8 +1,12 @@
 <!-- Android / Chrome PWA support -->
 <meta name="mobile-web-app-capable" content="yes">
-<meta name="background-color" content="{{ PWA_BG_COLOR }}">
+{% if PWA_THEME_COLOR %}
 <meta name="theme-color" content="{{ PWA_THEME_COLOR }}">
 <style>:root { --pwa-theme-colour: {{ PWA_THEME_COLOR }}; }</style>
+{% endif %}
+{% if PWA_BG_COLOR %}
+<meta name="background-color" content="{{ PWA_BG_COLOR }}">
+{% endif %}
 <!-- iOS PWA support -->
 <meta name="apple-mobile-web-app-capable" content="yes">
 <meta name="apple-mobile-web-app-title" content="{{ SHORT_SITE_NAME }}">
diff --git a/tests/controller/controller_manifest_test.php b/tests/controller/controller_manifest_test.php
index 03258f7..874153e 100644
--- a/tests/controller/controller_manifest_test.php
+++ b/tests/controller/controller_manifest_test.php
@@ -36,6 +36,8 @@ protected function setUp(): void
 		$lang_loader = new \phpbb\language\language_file_loader($phpbb_root_path, $phpEx);
 		$language = new \phpbb\language\language($lang_loader);
 		$user = $this->user = new \phpbb\user($language, '\phpbb\datetime');
+		$this->user->style['pwa_theme_color'] = '#000000';
+		$this->user->style['pwa_bg_color'] = '#ffffff';
 
 		$this->manifest = new \phpbb\webpushnotifications\controller\manifest($this->config, $this->user);
 	}
diff --git a/tests/event/listener_test.php b/tests/event/listener_test.php
index 1bba37f..e08c99c 100644
--- a/tests/event/listener_test.php
+++ b/tests/event/listener_test.php
@@ -349,8 +349,8 @@ public function test_pwa_manifest()
 				'U_MANIFEST_URL'	=> $this->controller_helper->route('phpbb_webpushnotifications_manifest_controller'),
 				'U_TOUCH_ICON'		=> ext::PWA_ICON_DIR . '/icon-192x192.png',
 				'SHORT_SITE_NAME'	=> 'Test',
-				'PWA_THEME_COLOR'	=> ext::PWA_THEME_COLOR,
-				'PWA_BG_COLOR'		=> ext::PWA_BG_COLOR,
+				'PWA_THEME_COLOR'	=> '',
+				'PWA_BG_COLOR'		=> '',
 				'S_PWA_SHOW_BANNER'	=> false,
 			]);
 
diff --git a/tests/functional/functional_test.php b/tests/functional/functional_test.php
index 9ad95c6..b4bb6f2 100644
--- a/tests/functional/functional_test.php
+++ b/tests/functional/functional_test.php
@@ -133,6 +133,8 @@ public function test_manifest()
 
 		$form_data = [
 			'config[pwa_short_name]'	=> $expected['short_name'],
+			'pwa_theme_color_1'	=> $expected['theme_color'],
+			'pwa_bg_color_1'	=> $expected['background_color'],
 		];
 		$form = $crawler->selectButton('submit')->form($form_data);
 		$crawler = self::submit($form);