Privacy Policy
JSON / API Viewer Pro — browser extension for Chrome, Microsoft Edge and Firefox · Effective date: 2 October 2026
Summary
The extension is local-first. The JSON documents, API responses, queries, schemas and settings you work with stay in your browser. There is no account, no analytics, no telemetry, no advertising and no server of ours that receives your data. We do not sell or share user data.
Permissions and why they are needed
| Permission | Purpose |
|---|---|
storage, unlimitedStorage | Save settings locally, and store your documents and snapshots in the browser's IndexedDB so large JSON files fit. |
activeTab, scripting | Only when you click “Open this tab's JSON” in the popup: read the text of the current tab to open it in the workbench. scripting also registers the optional JSON-page detector described below. |
contextMenus | Add “Open selection in JSON Workbench” to the right-click menu. |
sidePanel (Chrome, Edge) / sidebar (Firefox) | Open the workbench next to the page. |
| DevTools page | The “JSON API” DevTools panel lists JSON responses of the inspected tab while DevTools is open. Responses are kept in memory and saved only when you click Save snapshot or Open. |
| Access to websites (optional) | Never granted at install. Requested only when you turn on “Detect JSON pages” (all sites), or open a URL or replay a request from the workbench (only that site). You can revoke it any time on the browser's extensions page. |
api.lemonsqueezy.com | Activate and validate a Pro license key. |
Data stored on your device
- Documents you open, paste, import (including HAR files) or capture, and their request metadata (URL, method, status, headers) for API snapshots. Sensitive headers and keys (authorization, cookie, token, password…) are redacted before saving when “Redact secrets before saving” is on (default), and always for imported HAR files and replayed requests.
- Saved queries, query history, saved comparison pairs, schemas, endpoint baselines and settings (including any custom CSS you write).
- Onboarding and rating-prompt state (dates and counters only).
- If you buy Pro: the license key, activation instance id, plan and last validation time.
Data sent off your device
- License (Pro only). The license key, the activation instance id and an instance name made of the browser name and major version (for example
firefox-141) are sent to Lemon Squeezy, our payment provider and merchant of record, to activate and periodically validate the license. Checkout, subscription management (including cancelling auto-renew) and the affiliate program run on Lemon Squeezy's hosted pages; the extension never sees card details or affiliate data. - Requests you make yourself. Opening a URL in the workbench, replaying a captured request, or clicking “Preview image” on an image URL contacts that address directly from your browser, like visiting it. Replayed requests are sent without cookies. Nothing is routed through us.
JSON content, captured responses and everything else listed above are never sent anywhere by the extension.
Retention and deletion
On the Free plan the oldest non-favorite documents and snapshots are removed automatically beyond the plan limit. Otherwise data stays until you delete it. Settings → Delete all local data erases every document, snapshot and setting. Uninstalling the extension removes everything too. Backups are created only when you click Export.
Changes
If this policy changes, the effective date above changes with it. Material changes are noted in the extension's release notes.
Contact
Questions or requests: open an issue on GitLab.