POM upload screen says file:// URLs are supported but fails if you try one

The POM upload screen lists file:// among the supported URL types. However, any file:// URL that you try results in a misleading error message.

In fact, the "file" protocol is disabled by default.

This screen should explain that "file" must be manually enabled, and the resulting error message should say that the "file" protocol is disabled. Ideally it would point you to the correct place to enable it, and mention that until you've started continuum for the first time, the config file you need to edit won't be there (the JAR has to be unpacked first).