WebMargin does not collect, transmit, sell, or share user data. The extension contains no advertising, analytics, accounts, or network requests to the developer or third parties.

The extension reads the active tab's address, title, and browser-provided icon only to attach and display a local note. Note contents, formatting, tags, favorites, settings, and trash are stored exclusively in the browser profile's local extension storage.

Users can delete notes, restore them from trash, delete them permanently, or remove all extension data through the browser settings. Items in trash are automatically deleted after 30 days.

Backups are created only after an explicit user action and downloaded as local JSON files. WebMargin never uploads backup files or their contents.