It is possible to clear the name of a folder by renaming it to "" and files can be renamed to only contain a valid extension (".js", ".css" etc.).
Moreover two or more folders with an empty name ("") can be contained in the same folder which will probably cause issues.

Looks like a bug to me , will fix this soon!
thanks for reporting! this is a bug and i can reproduce.
@catarak I think just adding a length cap might work?
I think as discussed on https://github.com/processing/p5.js-web-editor/pull/962#issuecomment-475330642 we should also add some validations at the backend and s3
i think there should be frontend and backend validations.
I'm a first time contributor, is this still open for me to work on?
Hey sure , go for it ! What you need to do to counter this one.
If you have any doubt , most people here will be happy to help(or just tag me).
Congratulations of your first oss project.
Cheers!
Most helpful comment
Looks like a bug to me , will fix this soon!