TYPO3 Core

When trying to setup the latest TYPO3 V11 with composer req typo3/cms-base-distribution ^11.1 the install tool gets stuck on step 3 (Select a database - Use an existing empty database). The test table ( t3install_test_table ) gets created but the wizard remains on step 3 with the notification

Selected database is not empty!
Cannot use database "pp11_buechler", because it already contains tables. Please select a different database or choose to create one!

The following entry is added to the log file:

Wed, 14 Apr 2021 13:55:50 +0200 [CRITICAL] request="b7f8cda1a22f4" component="TYPO3.CMS.Core.Error.ProductionExceptionHandler": Core: Exception handler (WEB): Uncaught TYPO3 Exception: Return value of TYPO3\CMS\Core\Database\Connection::select() must implement interface Doctrine\DBAL\Driver\Statement, instance of Doctrine\DBAL\ForwardCompatibility\Result returned | TypeError thrown in file [server]/public/typo3/sysext/core/Classes/Database/Connection.php in line 277. Requested URL: http://domain.com/typo3/install.php - {"TYPO3_MODE":"BE","exception":{}}