Markdown LibraryLast updated: October 4, 2026
Markdown Library ML-42 ("the App") is a native macOS markdown editor and file browser. This Privacy Policy explains how we handle your data. The short version: your files stay on your Mac, and we collect nothing unless you choose to send us feedback.
Your files stay yours
ML-42 reads and writes files on your local filesystem. It does not upload, sync, or transmit your files anywhere. We have no access to your documents, folders, or edits.
Data that stays on your device
All data in ML-42 is stored locally on your Mac:
Your markdown files
What: The .md and .mdx files you open and edit
Purpose: Core functionality: reading, editing, and browsing markdown
Storage: Remain on your filesystem exactly where they are. ML-42 does not copy, move, or import them.
App preferences
What: Editor settings (font, size, spacing, appearance), workspace bookmarks, favorites, recent files
Purpose: Remembering your configuration between sessions
Storage: Stored in the app's local container via UserDefaults and SwiftData
Workspace bookmarks
What: Security-scoped bookmarks for folders you've opened
Purpose: Maintaining sandboxed access to your project folders between launches
Storage: Stored locally in the app's SwiftData database
File access
ML-42 is a sandboxed macOS application. It can only access folders you explicitly grant permission to via the system file picker. Access is maintained between sessions using Apple's security-scoped bookmarks.
- ML-42 reads markdown files to display their content
- ML-42 writes to files when you edit them (auto-saved after a short pause)
- ML-42 creates new files and folders when you use the New Document or New Folder commands
- ML-42 can rename and delete files and folders at your request
ML-42 does not access files outside the folders you have opened as projects.
Network use
ML-42 goes online for two things only.
Images with web addresses
What: When a document you view contains an image whose address starts with http or https, ML-42 downloads that image from its server to show it in view mode, the way a web browser would.
Who sees it: The server that hosts the image receives a request from your Mac, which includes your IP address and the image address. ML-42 sends nothing else, and none of your document text.
When: Only for documents that link to images on the web. Images stored in your folders are read from disk.
The feedback form
What: When you send feedback from Help › Send Feedback, ML-42 sends your message, the category you pick, your email address if you enter one, and, unless you turn the option off, your macOS version and the app version, to our server at fieldbw.com.
When: Nothing is sent until you send the form.
Apart from these there is no telemetry, no analytics, no crash reporting, no update checking, and no cloud sync. Everything else in the app works offline.
No accounts
ML-42 does not require or support user accounts, sign-in, or registration.
AI features
ML-42 may use Apple's on-device FoundationModels for optional features like document summaries. When available, this processing runs entirely on your hardware using Apple's local models. No data is sent to cloud AI services.
Third-party services
ML-42 does not integrate with any third-party services. It does not include advertising SDKs, analytics frameworks, or tracking pixels. The only other servers it contacts are the ones that host images your documents link to.
Children's privacy
ML-42 collects nothing from anyone, including children, beyond feedback a user chooses to send. The app has no age restrictions beyond macOS system requirements.
Changes to this policy
We may update this Privacy Policy from time to time. Changes will be posted on this page with an updated date. Your continued use of the App constitutes acceptance of any changes.
Contact
Questions about this policy? Contact us at our support page.
This Privacy Policy is effective as of October 4, 2026.