diff --git a/Classes/Core/Acceptance/Extension/BackendEnvironment.php b/Classes/Core/Acceptance/Extension/BackendEnvironment.php
index 758e936e..2c41795f 100644
--- a/Classes/Core/Acceptance/Extension/BackendEnvironment.php
+++ b/Classes/Core/Acceptance/Extension/BackendEnvironment.php
@@ -21,7 +21,9 @@
 use Codeception\Events;
 use Codeception\Extension;
 use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Utility\ArrayUtility;
 use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\TestingFramework\Composer\ComposerPackageManager;
 use TYPO3\TestingFramework\Core\Functional\Framework\DataHandling\DataSet;
 use TYPO3\TestingFramework\Core\Testbase;
 
@@ -147,6 +149,19 @@ abstract class BackendEnvironment extends Extension
          * Example: [ __DIR__ . '/../../Fixtures/BackendEnvironment.csv' ]
          */
         'csvDatabaseFixtures' => [],
+
+        /**
+         * Copy files within created test instance.
+         *
+         * @var array<string, string[]>
+         */
+        'copyInstanceFiles' => [],
+
+        /**
+         * Should target paths for self::$config['copyInstanceFiles'] be created.
+         * Will throw an exception if folder does not exists and set to `false`.
+         */
+        'copyInstanceFilesCreateTargetPath' => true,
     ];
 
     /**
@@ -170,6 +185,11 @@ abstract class BackendEnvironment extends Extension
         Events::TEST_BEFORE => 'cleanupTypo3Environment',
     ];
 
+    /**
+     * @var string|null Test instance path when created.
+     */
+    protected ?string $instancePath = null;
+
     /**
      * Initialize config array, called before events.
      *
@@ -230,7 +250,7 @@ public function bootstrapTypo3Environment(SuiteEvent $suiteEvent)
         $testbase->createDirectory(ORIGINAL_ROOT . 'typo3temp/var/tests/acceptance');
         $testbase->createDirectory(ORIGINAL_ROOT . 'typo3temp/var/transient');
 
-        $instancePath = ORIGINAL_ROOT . 'typo3temp/var/tests/acceptance';
+        $instancePath = $this->instancePath = ORIGINAL_ROOT . 'typo3temp/var/tests/acceptance';
         putenv('TYPO3_PATH_ROOT=' . $instancePath);
         putenv('TYPO3_PATH_APP=' . $instancePath);
         $testbase->setTypo3TestingContext();
@@ -303,6 +323,13 @@ public function bootstrapTypo3Environment(SuiteEvent $suiteEvent)
         // @todo: See which other possible state should be dropped here again (singletons, ...?)
         restore_error_handler();
 
+        $this->applyDefaultCopyInstanceFilesConfiguration();
+        $copyInstanceFilesCreateTargetPaths = (bool)($this->config['copyInstanceFilesCreateTargetPath'] ?? true);
+        $copyInstanceFiles = $this->config['copyInstanceFiles'] ?? [];
+        if (is_array($copyInstanceFiles) && $copyInstanceFiles !== []) {
+            $testbase->copyInstanceFiles($instancePath, $copyInstanceFiles, $copyInstanceFilesCreateTargetPaths);
+        }
+
         // Unset a closure or phpunit kicks in with a 'serialization of \Closure is not allowed'
         // Alternative solution:
         // unset($GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['GLOBAL']['cliKeys']['extbase']);
@@ -328,4 +355,94 @@ public function cleanupTypo3Environment()
             ->getConnectionForTable('be_users')
             ->update('be_users', ['uc' => null], ['uid' => 1]);
     }
+
+    private function applyDefaultCopyInstanceFilesConfiguration(): void
+    {
+        if ($this->hasExtension('typo3/cms-backend')) {
+            ArrayUtility::mergeRecursiveWithOverrule(
+                $this->config,
+                [
+                    'copyInstanceFiles' => [
+                        // Create favicon.ico to suppress potential javascript errors in console
+                        // which are caused by calling a non html in the browser, e.g. seo sitemap xml
+                        'typo3/sysext/backend/Resources/Public/Icons/favicon.ico' => [
+                            'favicon.ico',
+                        ],
+                    ],
+                ]
+            );
+        }
+        if ($this->hasExtension('typo3/cms-install')) {
+            ArrayUtility::mergeRecursiveWithOverrule(
+                $this->config,
+                [
+                    'copyInstanceFiles' => [
+                        // Provide some files into the test instance normally added by installer
+                        'typo3/sysext/install/Resources/Private/FolderStructureTemplateFiles/root-htaccess' => [
+                            '.htaccess',
+                        ],
+                        'typo3/sysext/install/Resources/Private/FolderStructureTemplateFiles/resources-root-htaccess' => [
+                            'fileadmin/.htaccess',
+                        ],
+                        'typo3/sysext/install/Resources/Private/FolderStructureTemplateFiles/fileadmin-temp-htaccess' => [
+                            'fileadmin/_temp_/.htaccess',
+                        ],
+                        'typo3/sysext/install/Resources/Private/FolderStructureTemplateFiles/fileadmin-temp-index.html' => [
+                            'fileadmin/_temp_/index.html',
+                        ],
+                        'typo3/sysext/install/Resources/Private/FolderStructureTemplateFiles/typo3temp-var-htaccess' => [
+                            'typo3temp/var/.htaccess',
+                        ],
+                    ],
+                ]
+            );
+        }
+    }
+
+    /**
+     * Verify if extension is available in the system and within the acceptance test instance.
+     */
+    protected function hasExtension(string $extensionKeyOrComposerPackageName): bool
+    {
+        $instanceExtensions = $this->getInstanceExtensionKeys(
+            $this->config['coreExtensionsToLoad'],
+            $this->config['testExtensionsToLoad'],
+        );
+        $packageInfo = (new ComposerPackageManager())->getPackageInfo($extensionKeyOrComposerPackageName);
+        if ($packageInfo === null) {
+            return false;
+        }
+        return $packageInfo->getExtensionKey() !== '' && in_array($packageInfo->getExtensionKey(), $instanceExtensions, true);
+    }
+
+    /**
+     * Gather list of extension keys available within created test instance
+     * based on `coreExtensionsToLoad` and `testExtensionToLoad` config.
+     */
+    private function getInstanceExtensionKeys(
+        array $coreExtensionsToLoad,
+        array $testExtensionsToLoad,
+    ): array {
+        $composerPackageManager = new ComposerPackageManager();
+        if ($coreExtensionsToLoad === []) {
+            // Fallback to all system extensions needed for TYPO3 acceptanceInstall tests.
+            $coreExtensionsToLoad = $composerPackageManager->getSystemExtensionExtensionKeys();
+        }
+        $result = [];
+        foreach ($coreExtensionsToLoad as $extensionKeyOrComposerPackageName) {
+            $packageInfo = $composerPackageManager->getPackageInfo($extensionKeyOrComposerPackageName);
+            if ($packageInfo === null || $packageInfo->getExtensionKey() === '') {
+                continue;
+            }
+            $result[] = $packageInfo->getExtensionKey();
+        }
+        foreach ($testExtensionsToLoad as $extensionKeyOrComposerPackageName) {
+            $packageInfo = $composerPackageManager->getPackageInfo($extensionKeyOrComposerPackageName);
+            if ($packageInfo === null || $packageInfo->getExtensionKey() === '') {
+                continue;
+            }
+            $result[] = $packageInfo->getExtensionKey();
+        }
+        return $result;
+    }
 }
diff --git a/Classes/Core/Testbase.php b/Classes/Core/Testbase.php
index eafdb12f..839af1d8 100644
--- a/Classes/Core/Testbase.php
+++ b/Classes/Core/Testbase.php
@@ -199,7 +199,7 @@ public function setUpInstanceCoreLinks(
 
         $linksToSet = [];
         $coreExtensions = array_unique(array_merge($defaultCoreExtensionsToLoad, $coreExtensionsToLoad));
-        // @todo Fallback to all system extensions needed for TYPO3 acceptanceInstall tests.
+        // Fallback to all system extensions needed for TYPO3 acceptanceInstall tests.
         if ($coreExtensions === []) {
             $coreExtensions = $this->composerPackageManager->getSystemExtensionExtensionKeys();
         }
@@ -269,6 +269,46 @@ public function setUpInstanceCoreLinks(
         }
     }
 
+    public function provideInstance(array $additionalHtaccessFiles = []): void
+    {
+        $copyFiles = [
+            // Create favicon.ico to suppress potential javascript errors in console
+            // which are caused by calling a non html in the browser, e.g. seo sitemap xml
+            'typo3/sysext/backend/Resources/Public/Icons/favicon.ico' => [
+                'favicon.ico',
+            ],
+            // Provide some files into the test instance normally added by installer
+            'typo3/sysext/install/Resources/Private/FolderStructureTemplateFiles/root-htaccess' => [
+                '.htaccess',
+            ],
+            'typo3/sysext/install/Resources/Private/FolderStructureTemplateFiles/resources-root-htaccess' => [
+                'fileadmin/.htaccess',
+            ],
+            'typo3/sysext/install/Resources/Private/FolderStructureTemplateFiles/fileadmin-temp-htaccess' => [
+                'fileadmin/_temp_/.htaccess',
+            ],
+            'typo3/sysext/install/Resources/Private/FolderStructureTemplateFiles/fileadmin-temp-index.html' => [
+                'fileadmin/_temp_/index.html',
+            ],
+            'typo3/sysext/install/Resources/Private/FolderStructureTemplateFiles/typo3temp-var-htaccess' => [
+                'typo3temp/var/.htaccess',
+            ],
+        ];
+        foreach ($copyFiles as $sourceFile => $targetFiles) {
+            foreach ($targetFiles as $targetFile) {
+                $this->createDirectory(dirname(ltrim($targetFile, '/')));
+                $sourceFile = ltrim($sourceFile, '/');
+                $targetFile = ltrim($targetFile, '/');
+                if (!@copy($sourceFile, $targetFile)) {
+                    throw new \RuntimeException(
+                        sprintf('Could not copy "%s" to "%s".', $sourceFile, $targetFile),
+                        1733391799,
+                    );
+                }
+            }
+        }
+    }
+
     /**
      * Link test extensions to the typo3conf/ext folder of the instance.
      * For functional and acceptance tests.
@@ -978,4 +1018,110 @@ protected function exitWithMessage(string $message): never
         echo $message . chr(10);
         exit(1);
     }
+
+    /**
+     * Copy files within the test instance path `$instancePath`.
+     *
+     * @param string $instancePath The test instance path.
+     * @param array<string, string[]> $files
+     * @throws Exception
+     */
+    public function copyInstanceFiles(string $instancePath, array $files, bool $createTargetFolder = true): void
+    {
+        if ($files === []) {
+            return;
+        }
+        foreach ($files as $sourceFile => $targetFiles) {
+            foreach ($targetFiles as $targetFile) {
+                $this->copyInstanceFile($instancePath, $sourceFile, $targetFile, $createTargetFolder);
+            }
+        }
+    }
+
+    /**
+     * Copy one file within the test instance with the option to create the target path.
+     *
+     * @param string $instancePath The test instance path.
+     * @param string $sourceFile Relative source file path within test instance.
+     * @param string $targetFile Target file path within test instance.
+     * @param bool $createTargetFolder True to create target folder it does not exists, otherwise exception is thrown.
+     * @throws Exception
+     */
+    public function copyInstanceFile(string $instancePath, string $sourceFile, string $targetFile, bool $createTargetFolder = true): void
+    {
+        if (str_starts_with($sourceFile, '/')) {
+            throw new \RuntimeException(
+                sprintf(
+                    'Source "%s" must be relative from test instance path and must not start with "/".',
+                    $sourceFile,
+                ),
+                1733392183,
+            );
+        }
+        if (str_starts_with($targetFile, '/')) {
+            throw new \RuntimeException(
+                sprintf(
+                    'Target "%s" must be relative from test instance path and must not start with "/".',
+                    $targetFile,
+                ),
+                1733392258,
+            );
+        }
+        if (trim($sourceFile, '/') === '') {
+            throw new \RuntimeException(
+                sprintf(
+                    'Source "%s" must not be empty or "/".',
+                    $sourceFile,
+                ),
+                1733392321,
+            );
+        }
+        if (trim($targetFile, '/') === '') {
+            throw new \RuntimeException(
+                sprintf(
+                    'Target "%s" must not be empty or "/".',
+                    $targetFile,
+                ),
+                1733392321,
+            );
+        }
+        $instancePath = rtrim($instancePath, '/');
+        $sourceFileFull = $instancePath . '/' . $sourceFile;
+        $targetFileFull = $instancePath . '/' . $targetFile;
+        $targetPath = rtrim(dirname($targetFile), '/');
+        $targetPathFull = $instancePath . '/' . $targetPath;
+        if (!is_dir($targetPathFull)) {
+            if (!$createTargetFolder) {
+                throw new \RuntimeException(
+                    sprintf(
+                        'Target instance path "%s" does not exists and should not be created, but is required.',
+                        $targetPath,
+                    ),
+                    1733392917,
+                );
+            }
+            $this->createDirectory($targetPathFull);
+        }
+        if (!file_exists($sourceFileFull)) {
+            throw new \RuntimeException(
+                sprintf(
+                    'Source file "%s" does not exists within test instance "%s" and could not be copied to "%s".',
+                    $sourceFile,
+                    $instancePath,
+                    $targetFile,
+                ),
+                1733393186,
+            );
+        }
+        if (!@copy($sourceFileFull, $targetFileFull)) {
+            throw new \RuntimeException(
+                sprintf(
+                    'Could not copy "%s" to "%s".',
+                    $sourceFile,
+                    $targetFile,
+                ),
+                1733391799,
+            );
+        }
+    }
 }