I released JSONView in early 2009 to solve a simple problem I had - I’d been working with a number of JSON APIs, but Firefox had no way of directly viewing JSON documents. At the time, it wouldn’t even display them as text, showing a download dialog instead. Even after Firefox started showing JSON as text, it was still useful to show JSON nicely formatted and highlighted rather than however it was served. In the nearly eight years since its launch, JSONView has grown to about 130,000 daily users and has been downloaded 1.5 million times.

Once the initial few versions were out, I’ve updated JSONView on average every six months. Following that trend, I released JSONView 1.2.0 in late November. I’ve expected Firefox to subsume JSONView’s functionality ever since I first launched it, but amazingly this hasn’t happened yet. That said, Firefox has recently gained a very nice native JSON viewer hidden behind a developer flag (that’s only on by default in Firefox Developer Edition) and JSONView now offers the option of simply turning on that viewer instead of doing its own thing. Hopefully soon, JSONView won’t be needed at all.

I’ve always applied a minimalist philosophy to the extension. I’ve resisted adding a lot of bells and whistles in favor of a simple extension that does one thing well. This has the side-effect of reducing the rate of change of the extension, since besides the constant work of keeping it up to date with changes to Firefox, it’s pretty much done. There are still capabilities I’d like to add to JSONView, but those that haven’t already happened are usually impossible within the bounds of Firefox’s extension API. Speaking of which, Firefox is generally moving away from the sort of deep integration for extensions that JSONView requires - I hope JSONView is completely obviated by the time it can no longer work at all.

I personally don’t use JSONView anymore at all, because I no longer use Firefox. When I interact with JSON APIs I make use of the Chrome devtools, Emacs restclient-mode, and the jq and gron command-line tools. I’ve continued to maintain the extension, which remains open sourced on GitHub with several contributors helping out over time.

JSONView has been cloned, without permission (but without any resistance - it’s open source after all) as a Chrome extension in at least two instances. One of them became very popular but has been abandoned and is no longer on the Chrome web store because it contains security vulnerabilities. I never made a Chrome version myself because Chrome doesn’t offer the same integration APIs that Firefox does, so I couldn’t make it work the same way. JSONView for Firefox intercepts requests for JSON documents and produces HTML instead. The Chrome ports run on every single page that Chrome loads and try to figure out whether it looks like a JSON document, then reformats the document in-place. I never liked the security and performance implications of that, so I’ve avoided an official port. I keep an eye on Chrome’s extension API in case it ever becomes possible to do things the way I want to.

In summary, JSONView the Firefox extension is doing well, but is a mature project that will change slowly, if at all. JSONView for Chrome appears to be dead, and I don’t have immediate plans to produce an official port myself, but I won’t rule it out and I’d accept a well-implemented contribution as long as it matched the design and implementation philosophy of the original.