diff --git a/phpBB/config/default/container/services_assets.yml b/phpBB/config/default/container/services_assets.yml
index 1370a62062..6ba3a7ea27 100644
--- a/phpBB/config/default/container/services_assets.yml
+++ b/phpBB/config/default/container/services_assets.yml
@@ -4,4 +4,5 @@ services:
         arguments:
             - '@dbal.conn'
             - '@ext.manager'
+            - '@log'
             - '%core.root_path%'
diff --git a/phpBB/develop/create_iconify_bundle.php b/phpBB/develop/create_iconify_bundle.php
index 8d1c33fe8d..b71b2f30bd 100644
--- a/phpBB/develop/create_iconify_bundle.php
+++ b/phpBB/develop/create_iconify_bundle.php
@@ -34,9 +34,7 @@ $iconify_bundler->find_icons([
 	$phpbb_root_path . 'styles/',
 	$phpbb_root_path . 'adm/style/',
 ]);
-$output = $iconify_bundler->with_extensions()
-	->with_styles()
-	->run();
+$output = $iconify_bundler->get_bundle();
 
 // Save to file
 file_put_contents($target, $output);
diff --git a/phpBB/includes/acp/acp_extensions.php b/phpBB/includes/acp/acp_extensions.php
index 1a30d38d61..4e6b143713 100644
--- a/phpBB/includes/acp/acp_extensions.php
+++ b/phpBB/includes/acp/acp_extensions.php
@@ -270,6 +270,10 @@ class acp_extensions
 					), array($this->phpbb_root_path . 'adm/style'));
 
 					$this->log->add('admin', $this->user->data['user_id'], $this->user->ip, 'LOG_EXT_ENABLE', time(), array($ext_name));
+
+					// Force rebuild of iconify bundle
+					$iconify_bundler = new \phpbb\assets\iconify_bundler($this->db, $this->ext_manager, $this->log, $this->phpbb_root_path);
+					$iconify_bundler->get_bundle(true);
 				}
 				catch (\phpbb\db\migration\exception $e)
 				{
@@ -316,6 +320,10 @@ class acp_extensions
 				}
 				$this->log->add('admin', $this->user->data['user_id'], $this->user->ip, 'LOG_EXT_DISABLE', time(), array($ext_name));
 
+				// Force rebuild of iconify bundle
+				$iconify_bundler = new \phpbb\assets\iconify_bundler($this->db, $this->ext_manager, $this->log, $this->phpbb_root_path);
+				$iconify_bundler->get_bundle(true);
+
 				$this->tpl_name = 'acp_ext_disable';
 
 				$this->template->assign_vars([
diff --git a/phpBB/includes/acp/acp_styles.php b/phpBB/includes/acp/acp_styles.php
index a1b1e62a3b..6da638379c 100644
--- a/phpBB/includes/acp/acp_styles.php
+++ b/phpBB/includes/acp/acp_styles.php
@@ -65,6 +65,9 @@ class acp_styles
 	/** @var \phpbb\event\dispatcher_interface */
 	protected $dispatcher;
 
+	/** @var \phpbb\assets\iconify_bundler */
+	protected $iconify_bundler;
+
 	public function main($id, $mode)
 	{
 		global $db, $phpbb_admin_path, $phpbb_root_path, $phpEx, $template, $request, $cache, $auth, $config, $phpbb_dispatcher, $phpbb_container;
@@ -80,6 +83,7 @@ class acp_styles
 		$this->phpbb_root_path = $phpbb_root_path;
 		$this->php_ext = $phpEx;
 		$this->dispatcher = $phpbb_dispatcher;
+		$this->iconify_bundler = $phpbb_container->get('assets.iconify_bundler');
 
 		$this->default_style = $config['default_style'];
 		$this->styles_path = $this->phpbb_root_path . $this->styles_path_absolute . '/';
@@ -240,6 +244,9 @@ class acp_styles
 			$this->text_formatter_cache->invalidate();
 		}
 
+		// Force rebuild of iconify bundle
+		$this->iconify_bundler->get_bundle(true);
+
 		// Show message
 		if (!count($messages))
 		{
@@ -331,7 +338,7 @@ class acp_styles
 		$rows = $this->db->sql_fetchrowset($result);
 		$this->db->sql_freeresult($result);
 
-		// Uinstall each style
+		// Uninstall each style
 		$uninstalled = array();
 		foreach ($rows as $style)
 		{
@@ -367,6 +374,9 @@ class acp_styles
 		// Clear cache
 		$this->cache->purge();
 
+		// Force rebuild of iconify bundle
+		$this->iconify_bundler->get_bundle(true);
+
 		// Show message
 		trigger_error(implode('<br />', $messages) . adm_back_link($this->u_action), E_USER_NOTICE);
 	}
diff --git a/phpBB/language/en/acp/common.php b/phpBB/language/en/acp/common.php
index aeab0af262..bbe8b7fafa 100644
--- a/phpBB/language/en/acp/common.php
+++ b/phpBB/language/en/acp/common.php
@@ -671,6 +671,8 @@ $lang = array_merge($lang, array(
 	'LOG_USERS_APPROVED'	=> '<strong>Users approved in usergroup</strong> %1$s<br />» %2$s',
 	'LOG_USERS_PENDING'		=> '<strong>Users requested to join group “%1$s” and need to be approved</strong><br />» %2$s',
 
+	'LOG_ICON_INVALID'				=> '<strong>Invalid icon supplied:</strong> Icon <i>%1$s:%2$s</i> does not seem to exist.',
+	'LOG_ICON_COLLECTION_INVALID'	=> '<strong>Invalid icon collection supplied:</strong> Icon collection with prefix <i>%1$s</i> does not seem to exist.',
 	'LOG_IMAGE_GENERATION_ERROR'	=> '<strong>Error while creating image</strong><br />» Error in %1$s on line %2$s: %3$s',
 
 	'LOG_INACTIVE_ACTIVATE'	=> '<strong>Activated inactive users</strong><br />» %s',
diff --git a/phpBB/phpbb/assets/iconify_bundler.php b/phpBB/phpbb/assets/iconify_bundler.php
index 8bb77ea605..70e5d5f83b 100644
--- a/phpBB/phpbb/assets/iconify_bundler.php
+++ b/phpBB/phpbb/assets/iconify_bundler.php
@@ -19,21 +19,35 @@ use Symfony\Component\Finder\Finder;
 
 class iconify_bundler
 {
+	protected const BUNDLE_PATH = 'assets/iconify/iconify_bundle.js';
+
 	protected $db;
 
 	protected $ext_manager;
 
+	/** @var \phpbb\log\log_interface */
+	protected $log;
+
+	/** @var \phpbb\filesystem\filesystem_interface */
+	protected $filesystem;
+
 	protected $root_path = '';
+
+	protected $bundle_path = '';
 	protected $icons_list = [];
 
-	public function __construct(\phpbb\db\driver\driver_interface $db, \phpbb\extension\manager $ext_manager, string $root_path)
+	public function __construct(\phpbb\db\driver\driver_interface $db, \phpbb\extension\manager $ext_manager, \phpbb\log\log_interface $log, string $root_path)
 	{
 		$this->db = $db;
 		$this->ext_manager = $ext_manager;
+		$this->filesystem = new \phpbb\filesystem\filesystem();
+		$this->log = $log;
 		$this->root_path = $root_path;
+
+		$this->bundle_path = $root_path . self::BUNDLE_PATH;
 	}
 
-	public function run()
+	protected function run()
 	{
 		// Sort icons first
 		sort($this->icons_list, SORT_NATURAL);
@@ -62,6 +76,22 @@ class iconify_bundler
 		return $output;
 	}
 
+	public function get_bundle(bool $force_rebuild = false): string
+	{
+		if (!$force_rebuild && $this->is_dumped())
+		{
+			return file_get_contents($this->bundle_path);
+		}
+
+		$iconify_bundle = $this->with_extensions()
+			->with_styles()
+			->run();
+
+		$this->filesystem->dump_file($this->bundle_path, $iconify_bundle);
+
+		return $iconify_bundle;
+	}
+
 	/**
 	 * @param array $paths Icon paths
 	 *
@@ -157,6 +187,11 @@ class iconify_bundler
 		return $this;
 	}
 
+	protected function is_dumped(): bool
+	{
+		return $this->filesystem->exists($this->bundle_path) && $this->filesystem->is_readable($this->bundle_path);
+	}
+
 	protected function add_icon(string $icon_name): void
 	{
 		if (!in_array($icon_name, $this->icons_list))
@@ -276,18 +311,16 @@ class iconify_bundler
 		{
 			// Load icon set
 			$collection = new Collection($prefix);
-			if (!$collection->loadIconifyCollection($prefix)) {
-				throw new \Error(
-					'Icons with prefix "' . $prefix . '" do not exist in Iconify. Update iconify/json?'
-				);
+			if (!$collection->loadIconifyCollection($prefix))
+			{
+				$this->log->add('critical', ANONYMOUS, '', 'LOG_ICON_COLLECTION_INVALID', false, [$prefix]);
 			}
 
 			// Make sure all icons exist
 			foreach ($iconsList as $name) {
-				if (!$collection->iconExists($name)) {
-					// Uncomment next line to throw error if an icon does not exist
-					// throw new Error('Could not find icon: "' . $prefix . ':' . $name . '"');
-					echo 'Could not find icon: "', $prefix, ':', $name, "\"\n";
+				if (!$collection->iconExists($name))
+				{
+					$this->log->add('critical', ANONYMOUS, '', 'LOG_ICON_INVALID', false, [$prefix, $name]);
 				}
 			}
 
diff --git a/phpBB/styles/prosilver/template/overall_footer.html b/phpBB/styles/prosilver/template/overall_footer.html
index e095b3af2d..035748bc10 100644
--- a/phpBB/styles/prosilver/template/overall_footer.html
+++ b/phpBB/styles/prosilver/template/overall_footer.html
@@ -76,7 +76,7 @@
 <script src="{T_ASSETS_PATH}/javascript/core.js?assets_version={T_ASSETS_VERSION}"></script>
 <!-- INCLUDEJS forum_fn.js -->
 <!-- INCLUDEJS ajax.js -->
-<script src="{T_ASSETS_PATH}/iconify/iconify-bundle.js?assets_version={T_ASSETS_VERSION}"></script>
+<script src="{{ T_ASSETS_PATH ~ '/iconify/iconify-bundle.js?assets_version=' ~ T_ASSETS_VERSION }}"></script>
 <script src="{T_ASSETS_PATH}/iconify/iconify.min.js?assets_version={T_ASSETS_VERSION}"></script>
 
 <!-- IF S_COOKIE_NOTICE -->