UI is empty and there are errors about a mime type mismatch in the dev toolbar. How to fix?

I downloaded Hashicorp Vault. I “installed” it which is just unzipping the archive and moving the vault application to wherever I want to run it from. I also added the path to the PATHS environment variable so that I can run the vault command from anywhere. I ran “vault server -dev” and the server starts up in dev mode as you would expect. I opened a browser and navigated to Unfortunately, the UI is blank. I opened the developer toolbar in chrome and I see three error messages. THe first one is:

Refused to execute script from ‘’ because its MIME type (‘text/plain’) is not executable, and strict MIME type checking is enabled.

What newb mistake am I making?