View registered modules

When modules are registered, they get added to a global array called $GLOBALS['TBE_MODULES']. It contains the list of all registered modules, their configuration and the configuration of any existing navigation component (the components which may be loaded into the navigation frame).

$GLOBALS['TBE_MODULES'] can be explored using the System > Configuration module.

Exploring the TBE_MODULES array using the Configuration module

The list of modules is parsed by the class \TYPO3\CMS\Backend\Module\ModuleLoader.