Important: #107536 - Install Tool now adapts to backend login routing 

See forge#107536

Description 

The Install Tool now integrates with TYPO3's backend routing system instead of using a separate typo3/install.php file. This modernization improves consistency while maintaining full backward compatibility.

If the TYPO3 installation is not working properly, the Install Tool can now be accessed via the ?__typo3_install parameter behavior so that administrators rely on for system maintenance and recovery.

Impact 

For Administrators:

All existing workflows continue to work without changes. However, the Install Tool is now accessible via:

  • The __typo3_install parameter (e.g., https://example.com/?__typo3_install)
  • Backend routes like /typo3/install and /typo3/install.php keep working, if the $GLOBALS['TYPO3_CONF_VARS']['BE']['entryPoint'] is set, the Install Tool adapts accordingly.

System Recovery:

When TYPO3 installation is not set up or not working properly, the magic __typo3_install parameter still redirects to the installer/maintenance tool as before, ensuring administrators can always access system recovery tools.

Technical Benefits:

The Install Tool now uses the same routing infrastructure as the rest of the TYPO3 backend, creating a more unified and maintainable architecture while supporting the long-term goal of simplifying TYPO3's directory structure.

Migration 

No migration is required. All existing documentation, scripts, and workflows using the Install Tool continue to function without modification.