[BUGFIX] Fallback to empty array if ExportController receives no input

Resolves: #88968
Releases: master
Change-Id: I1cab8a60e5b562376f9ac6bb6836e949bb9b1b50
Reviewed-on: https://review.typo3.org/c/Packages/TYPO3.CMS/+/61502
Reviewed-by: Josef Glatz <josefglatz@gmail.com>
Reviewed-by: Pascal Querner <pq@paskl.de>
Reviewed-by: Andreas Fernandez <a.fernandez@scripting-base.de>
Tested-by: TYPO3com <noreply@typo3.com>
Tested-by: Pascal Querner <pq@paskl.de>
Tested-by: Andreas Fernandez <a.fernandez@scripting-base.de>

typo3/sysext/impexp/Classes/Controller/ExportController.php

@@ -109,7 +109,7 @@ public function mainAction(ServerRequestInterface $request): ResponseInterface
         );
 
         // Input data grabbed:
-        $inData = GeneralUtility::_GP('tx_impexp');
+        $inData = $request->getParsedBody()['tx_impexp'] ?? $request->getQueryParams()['tx_impexp'] ?? [];
         if (!array_key_exists('excludeDisabled', $inData)) {
             // flag doesn't exist initially; state is on by default
             $inData['excludeDisabled'] = 1;