TYPO3 Exception 1294587486

TYPO3 9.5.23 and the extension phpmyadmin 5.6.4 result in error message

Session already started by session_start(). Make sure no installed extension is starting a session in its :file:`ext_localconf.php` or :file:`ext_tables.php`.
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when logging in to Admin Tools (Maintenance, Settings, Update, Environment) in Backend.

Solution: uninstall phpmyadmin, delete cookies, re-login