We have a jquery/Razor front-end that has a ton of global JS state manipulation and a file called 'common.js' which is a dumping ground for almost any function used in two places regardless of what it does. Many things are reinvented wheels (badly) and the previous team left a ton of XSS vulnerabilities in on top of that. Language differences from the previous offshore team mean things are named strangely to me, but even then, there's sometimes bad names for variables and functions.

Does it still function? Sort of. But most of our bugs are front-end issues because it's difficult to reason about any of the control flow. It isn't just obsolete or an unpopular framework, it's bad code.

There's no way I'm going to stay quiet about rewriting something like that if I want to stay at the company (spoiler: I'm quiet about it) and I don't think anyone else should be quiet about it either. This shit causes stress.