Privacy Policy

This Privacy Policy describes how your information is collected, used, and shared when you install and use the MarkLens: Local Markdown Reader browser extension (the “Extension”).

1. Information We Collect

Specifically, the Extension may access and process the following types of data, all of which are kept locally:

1.1 Local File and Directory Access

When you choose to “Open File” or “Open Directory,” the Extension uses the browser’s native File System Access API (and falls back to <input type="file" webkitdirectory> on unsupported browsers) to read Markdown files from your local filesystem.

• Scope of access: The Extension can only read files and folders that you explicitly select via the browser’s native file/directory picker dialog.
• What is read: The text content of .md, .markdown, .mdown, .mkd, and .mdx files you open, along with directory structure metadata (file names, folder hierarchy), for the sole purpose of rendering the directory tree and Markdown content.
• Data retention: File contents and directory listings are processed in-memory only during an active session. They are never uploaded or transmitted anywhere.

1.2 User Preferences and Settings

The Extension stores the following user preferences locally using the browser’s localStorage API:

• UI theme preference (light / dark)
• Sidebar visibility state and width
• Document font size
• Code block auto-wrap setting
• Last active sidebar mode (directory tree / document outline / search)

1.3 Persisted Directory Handles

If you use the “Open Directory” feature, the Extension may persist a FileSystemDirectoryHandle reference in the browser’s IndexedDB. This reference is used solely to remember the last-opened directory so that subsequent “Open Directory” dialogs start from that location.

• This handle only functions within your browser on the same device.
• It is never shared, uploaded, or transmitted.
• You can clear it at any time via your browser’s “Site Data” / “Storage” settings for the Extension.

1.4 Content Script Injection on file:// URLs

The Extension injects content scripts into browser tabs opened to local Markdown files via the file:// protocol. This injection:

• Reads the raw Markdown text already displayed in the tab (served from your local filesystem by the browser).
• Replaces it with a styled, rendered Markdown view within the same tab.
• Does not read any other files on your system unless you explicitly grant access via the directory picker.

2. What We Do NOT Do

MarkLens does not:

• Collect any personally identifiable information (PII)
• Require or perform user registration, login, or authentication
• Send any data to external servers, APIs, or third parties
• Use any analytics, telemetry, tracking, or crash-reporting services
• Show advertisements of any kind
• Set or read third-party cookies
• Access your browsing history, bookmarks, passwords, or other browser data beyond what is explicitly described above

3. Data Sharing and Disclosure

Because the Extension does not collect or transmit data off your device, there is no data to share, sell, or disclose to any third party.

4. Data Retention and Deletion

All data maintained by the Extension is stored locally in your browser and can be fully removed at any time by:

1. Uninstalling the Extension — This removes all localStorage and IndexedDB data associated with the Extension.
2. Clearing site storage — In your browser settings, navigate to the Extension’s storage settings and delete stored data.
3. Individual preference reset — Use the “Reset to Defaults” button in the Extension’s Settings panel, where available.

The Extension does not retain any copies of your data once it is removed from your browser.

5. Required Permissions

The Extension requests the following Chrome permissions, each used only for the purposes described:

No storage, scripting, host_permissions (http/https), or other broad permissions are requested.

6. Children’s Privacy

The Extension is not directed to children under the age of 13, and we do not knowingly collect personal information from children under 13.

7. Changes to This Privacy Policy

We may update this Privacy Policy from time to time to reflect changes to our practices or for other operational, legal, or regulatory reasons. The “Last updated” date at the top of this document will be revised accordingly.

8. Contact Us

If you have questions or concerns about this Privacy Policy, please open an issue in the Extension’s public repository or contact the developer via the support channels listed on the Extension’s Chrome Web Store listing.