[BUGFIX] do not use IconRegistry in ext_localconf.php

Build/phpstan-baseline.neon

@@ -59,3 +59,7 @@ parameters:
 			message: "#^Call to an undefined method TYPO3\\\\CMS\\\\Core\\\\Database\\\\Query\\\\QueryBuilder\\:\\:add\\(\\)\\.$#"
 			count: 1
 			path: ../Classes/ViewHelpers/GetDatabaseRecordViewHelper.php
+		-
+			message: "#^Class TYPO3\\\\CMS\\\\Core\\\\Imaging\\\\IconProvider\\\\FontawesomeIconProvider not found\\.$#"
+			count: 2
+			path: ../Classes/Listener/BootCompleted.php

Build/phpstan-baseline12.neon

@@ -77,4 +77,8 @@ parameters:
 		-
 			message: "#^Parameter \\$record of method B13\\\\Backendpreviews\\\\Service\\\\DatabaseRowService\\:\\:getAdditionalDataForView\\(\\) has invalid type TYPO3\\\\CMS\\\\Core\\\\Domain\\\\RecordInterface\\.$#"
 			count: 1
-			path: ../Classes/Service/DatabaseRowService.php
+			path: ../Classes/Service/DatabaseRowService.php
+		-
+			message: "#^Class TYPO3\\\\CMS\\\\Core\\\\Imaging\\\\IconProvider\\\\FontawesomeIconProvider not found\\.$#"
+			count: 2
+			path: ../Classes/Listener/BootCompleted.php

Build/phpstan-baseline13.neon

@@ -12,4 +12,8 @@ parameters:
 		-
 			message: "#^Parameter \\#2 \\$row of method TYPO3\\\\CMS\\\\Core\\\\Authentication\\\\BackendUserAuthentication\\:\\:recordEditAccessInternals\\(\\) expects array, TYPO3\\\\CMS\\\\Core\\\\Domain\\\\RecordInterface given\\.$#"
 			count: 1
-			path: ../Classes/Service/DatabaseRowService.php
+			path: ../Classes/Service/DatabaseRowService.php
+		-
+			message: "#^Class TYPO3\\\\CMS\\\\Core\\\\Imaging\\\\IconProvider\\\\FontawesomeIconProvider not found\\.$#"
+			count: 2
+			path: ../Classes/Listener/BootCompleted.php

Classes/Listener/BootCompleted.php

@@ -0,0 +1,45 @@
+<?php
+
+declare(strict_types=1);
+
+namespace B13\Backendpreviews\Listener;
+
+/*
+ * This file is part of TYPO3 CMS-extension backendpreviews by b13.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ */
+
+use TYPO3\CMS\Core\Core\Event\BootCompletedEvent;
+use TYPO3\CMS\Core\Imaging\IconRegistry;
+use TYPO3\CMS\Core\Package\PackageManager;
+
+class BootCompleted
+{
+    public function __construct(protected IconRegistry $iconRegistry, protected PackageManager $packageManager)
+    {
+    }
+
+    public function __invoke(BootCompletedEvent $event): void
+    {
+        if (!$this->packageManager->isPackageActive('fontawesome_provider')) {
+            return;
+        }
+        $this->iconRegistry->registerIcon(
+            'exclamation-triangle',
+            \TYPO3\CMS\Core\Imaging\IconProvider\FontawesomeIconProvider::class,
+            [
+                'name' => 'exclamation-triangle',
+            ]
+        );
+        $this->iconRegistry->registerIcon(
+            'exclamation-circle',
+            \TYPO3\CMS\Core\Imaging\IconProvider\FontawesomeIconProvider::class,
+            [
+                'name' => 'exclamation-circle',
+            ]
+        );
+    }
+}

Configuration/Services.yaml

@@ -15,3 +15,7 @@ services:
       - name: event.listener
         event: TYPO3\CMS\Backend\View\Event\PageContentPreviewRenderingEvent
         identifier: 'b13-backendpreview-page-content-preview-rendering'
+  B13\Backendpreviews\Listener\BootCompleted:
+    tags:
+      - name: event.listener
+        identifier: 'b13-backendpreview-boot-completed'

ext_localconf.php

@@ -11,10 +11,7 @@
 // if TYPO3 > 11 "$GLOBALS['TCA']['tt_content']['ctrl']['previewRenderer']" is always used for Backend-Preview-Rendering
 // extending the database row is handled by B13\Backendpreviews\Listener\PageContentPreviewRendering
 
-if (
-    (\TYPO3\CMS\Core\Utility\GeneralUtility::makeInstance(\TYPO3\CMS\Core\Information\Typo3Version::class))->getMajorVersion() < 12 ||
-    (\TYPO3\CMS\Core\Utility\GeneralUtility::makeInstance(\TYPO3\CMS\Core\Package\PackageManager::class)->isPackageActive('fontawesome_provider'))
-) {
+if ((new \TYPO3\CMS\Core\Information\Typo3Version())->getMajorVersion() < 12) {
     $iconRegistry = \TYPO3\CMS\Core\Utility\GeneralUtility::makeInstance(\TYPO3\CMS\Core\Imaging\IconRegistry::class);
     $iconRegistry->registerIcon(
         'exclamation-triangle',