Diagram Lens — Privacy Policy
Diagram Lens is a browser extension made by Northfield Apps that renders diagram code blocks on GitHub pages as inline SVG images. This policy explains what data the extension handles and how it is used.
Data we do not collect
The extension does not collect, transmit, or store any of the following:
- Your browsing history
- Any personal identifiers (name, email, IP address, device ID)
- Analytics or usage telemetry of any kind
Diagram rendering via Kroki
When a diagram code block is rendered, the extension sends the diagram source code to kroki.io, a third-party rendering service, over HTTPS. Kroki returns an SVG image that is displayed inline on the page.
No account or API key is required. The only data sent to Kroki is the diagram source code itself — no page URLs, user identifiers, or GitHub content outside the code block are included in the request. Kroki’s own privacy policy governs how they handle data on their end.
If you prefer that diagram source code not leave your browser, you can disable rendering for individual formats or turn the extension off entirely using the toolbar icon.
Voluntary bug reports
The extension includes an optional bug report form. If you choose to submit a report, the following information is sent to Northfield Apps:
- A description of the issue you provide
- An optional free-text message you write
Submission is always manual and requires you to click the Submit button. Nothing is sent automatically or in the background.
Reports are transmitted via Web3Forms and delivered to the developer’s email inbox. They are used solely to improve the extension and are not shared with third parties, not sold, and not linked to any personal identity.
Local storage
The extension stores your settings (such as enabled formats, render mode, and theme preference) in your browser’s local extension storage. These values never leave your device.
Third-party services
- Kroki — receives diagram source code when a block is rendered. See kroki.io.
- Web3Forms — receives report submissions when you voluntarily submit the bug report form. See their privacy policy at web3forms.com/privacy.
Children’s privacy
The extension is not directed at children under 13. We do not knowingly collect any information from children.
Changes to this policy
If this policy changes materially, the updated version will be posted at this URL with a revised date at the top.