All those stupid front end libraries will be the new mainframe. >Guys I’ve been stuck with this application that says its a web app doesn’t render in the brows

All those stupid front end libraries will be the new mainframe. >Guys I’ve been stuck with this application that says its a web app doesn’t render in the browser engine. It has its own version of a browser engine that’s from thirty years ago and it needs 200 dependencies from a repository that doesn’t exist anymore. How am I supposed to maintain this?