Firefox typically prompts users to download JSON files, but this add-on enables you to view them within your Firefox browser. Rather than prompting you to download them and then reopen them with the proper program, you can see them displayed just as you would XML documents. The view includes highlights and formatting and lets you collapse objects. In the event that there are errors within the document, you can still see the text. You can see how the extension works at http://jsonview.com/example.json.
Download and view JSON documents directly in your browser