Users manual 

• Install the extension from the TYPO3 Extension Repository or composer (package name: mediaessenz/diskusage)
• Open the file list module, choose a storage folder and click on the disk usage button in the docheader to see the disk usage of all underlying files (incl. subfolders)
• For files with references double click it to get detail infos
• For files without references click on it and choose "More Info" or "Delete"
• Restrict the result to only not referenced files by clicking on the corresponding button. This is useful to find no more needed big files quickly and easy
• Beside the folder tree, it is also possible to get deeper into a directory by double clicking the corresponding group header
• Use the breadcrumb above the chart to get back to a higher level, including the parent folders of the current folder
• Be sure to update your reference index, before deleting any files!!!
• Also keep in mind, that some files maybe linked directly and therefore have no references!