Breaking: #88376 - Removed obsolete "pageNotFound_handling" settings

Description

The following global TYPO3 settings, usually set within LocalConfiguration.php have been removed:

• $GLOBALS['TYPO3_CONF_VARS']['FE']['pageNotFound_handling']
• $GLOBALS['TYPO3_CONF_VARS']['FE']['pageNotFound_handling_statheader']
• $GLOBALS['TYPO3_CONF_VARS']['FE']['pageNotFound_handling_accessdeniedheader']
• $GLOBALS['TYPO3_CONF_VARS']['FE']['pageUnavailable_handling']
• $GLOBALS['TYPO3_CONF_VARS']['FE']['pageUnavailable_handling_statheader']

These settings are effectively replaced by the error handling of the newly introduced Site Handling which is more flexible and robust, and is used instead of these options when Site Handling was enabled in TYPO3 v9. For TYPO3 v10 Site Handling is a requirement, making these options useless.

Impact

Setting any of the options will have no effect any more. Executing the Silent Upgrade Wizard will remove the settings automatically.

Affected Installations

Any TYPO3 installations having these settings overridden in LocalConfiguration.php file of an installation.

Migration

Access the install tool to automatically update the LocalConfiguration.php file and remove the settings.

Ensure to set up Site Handling with proper error handlers. Avoid accessing these settings but rather use the available \TYPO3\CMS\Frontend\Controller\ErrorController class, when trying to manually trigger a 404/500 in the Frontend (e.g. custom plugin) instead.