A few months ago, like many devs, I noticed something off about the JSON viewer extension I'd been using for years.
It had been quietly updated. The code went closed-source. Donation popups started appearing on unrelated pages including, in some reports, users' checkout pages. The maintainer had moved on, and the new owners had different priorities than "view JSON."
I uninstalled it. Then I went looking for an alternative.
The replacement options I found had their own problems. Some required <all_urls> permissions to do something that should only need access to the current tab. Some hadn't been updated in three years and choked on any JSON file over 5MB. Some quietly phoned home for "telemetry."
So I built my own. It took longer than I expected. Here's what I learned.
