Debugging my web app with JSON/Firefox - Firefox handling of JSON?
The JSONView Firefox extension is really nice.
It formats, highlights, etc...
The only drawback is that it requires the mime type to be set to "application/json"
.But it is not really a drawback for you, because based on your "answer" (which shouldn't be an answer) your problem is that the mime type is "application/json"
and as a result Firefox doesn't know what to do with it and downloads it instead of displaying.