This is truly dystopian. A ruling in Springer's favor here could imply that modifying anything on a webpage, even without distribution, would constitute a copyright violation (EDIT: only for material in which the copyright holder does not grant permission for the modification; so not libre licensed projects). Screen readers for blind people could be illegal, accessibility extensions for high contrast for those visually impaired could become illegal, even just extensions that change all websites to dark mode like Dark Reader could become illegal. What constitutes modification? Would zooming in on a website become illegal? Would translating a website to a different language become illegal? Where does this end?
This needs to be shot down.