{SafeJSON}

SafeJSON Extension: How It Works

The SafeJSON browser extension auto-detects and formats raw JSON responses on any URL. It formats the response in the current page and does not send page JSON through URL parameters. The source code is open and auditable on GitHub.

What the extension does

When you open a URL that returns raw JSON, most browsers show a wall of unformatted text. The SafeJSON extension detects JSON responses and renders them with syntax highlighting, collapsible tree view, and copy-to-clipboard in the current page.

The extension does not send page JSON through URL parameters. It reads the page content, formats it with browser JavaScript, and replaces the raw text display. When you click the extension icon, it opens the full SafeJSON toolkit in a new tab without a payload query string.

Permissions explained

clipboardWrite

Used only when you click the Copy button to copy formatted JSON to your clipboard. The extension never reads your clipboard. Writes happen only on your explicit action.

Content script / host access

The extension reads the current page only to detect and format JSON responses. No page content is stored, sent through URL parameters, or collected for analytics. The host permission scope is broad so the extension can format JSON on any URL you visit, but it only activates on pages that return JSON content.

Remote code

The SafeJSON extension does not load any remote code. All scripts are bundled with the extension package. The full source is available on GitHub under the MIT license — every line is auditable.

Ads and affiliate

The extension does not inject ads, affiliate links, checkout popups, or tracking scripts into any page. It does one thing: detects JSON and formats it locally. There is no pasted-content analytics, no advertising network, and no data broker integration.

How to verify

  1. Open any URL that returns raw JSON
  2. Open DevTools (F12) → Network tab
  3. The extension formats the JSON in the current page — check that it does not open SafeJSON with JSON in the URL
  4. For a stronger test, switch the Network tab to Offline mode before loading the page — the extension still works

Detailed verification guide: How to verify SafeJSON does not upload your JSON

Use the same DevTools approach to check online JSON tools

Source audit

The extension source code is in the same public repository as the web app. Every permission, content script, and formatting routine is auditable. View source on GitHub

Install

Edge Add-ons: Install from Microsoft Edge Add-ons

Chrome Web Store: Pending review. Until approved, you can install manually from source:

git clone https://github.com/Json-Lee-git/SafeJSON
# Open chrome://extensions → Enable Developer Mode
# Load unpacked → select the extension/ folder

FAQ

Does the extension upload JSON content?
No page JSON is sent through URL parameters. The extension detects raw JSON responses on the page and formats them using browser JavaScript. You can verify this by opening DevTools Network tab while the extension formats a JSON response.
Why does the extension need content script / host access?
The host permission allows the extension to detect raw JSON responses on any URL you visit. When it finds JSON, it formats it for readability in the current page. The extension does not send page JSON through URL parameters. It only reads the current page to check whether the response is JSON.
How can I verify the extension behavior?
Open DevTools (F12) and go to the Network tab. Visit any URL that returns raw JSON. The extension formats it and does not open SafeJSON with page JSON in the URL. For a stronger test, switch the Network tab to Offline mode before loading the page.

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