Privacy policy

Effective date: October 30, 2026. Applies to Margin versions 0.1.0 and 0.1.1.

What Margin handles locally

To provide its two features, Margin examines the structure of the rendered Substack page: feed-card labels, authored-content links, article-preview indicators, loading state, media presence and navigation-control labels. The links it examines may incidentally include usernames or other identifiers already present in the page.

Margin also reads the current Substack page URL to recognize Home and client-side navigation. This is not a recorded history of the sites you visit. Page information and references to affected elements are handled temporarily in the browser; Margin does not save copies of Notes, articles, profiles or browsing history.

What is saved

Margin stores two boolean preferences using Chrome's chrome.storage.local API:

• hideStandaloneNotes: whether to hide standalone Notes.
• hideNotesShortcuts: whether to hide Notes-specific navigation shortcuts.

Both default to enabled. Margin does not use Chrome sync storage. The preferences are not credentials or secrets; they are stored in the extension's local browser-profile storage, not a separate encrypted account or vault.

Website access and scope

Chrome grants the content scripts access to HTTPS pages on substack.com and www.substack.com. Scripts can be injected on all paths of those hosts. Selective feed filtering applies only to Home, and the extension excludes /publish editor routes from its hiding behaviors.

Margin does not request access to unrelated websites, individual publication subdomains or custom publication domains. It can recognize an article link to such a domain while that link appears on the Substack page; it does not open or fetch the destination to inspect it.

Margin changes visibility with reversible CSS classes. It does not delete or publish content, change your account, rewrite links, or block the Notes URL.

No transmission, tracking or advertising

The extension has no backend, telemetry, analytics, advertising, affiliate tracking, remote code or remotely loaded fonts. It does not use cookies, read authentication credentials, or send extension-handled information to the developer or third parties.

Substack and Chrome continue to perform their own ordinary network activity. That activity is separate from Margin. The extension's local processing does not prevent Substack from receiving the information it normally receives when you use its service.

Use and sharing

Margin uses locally handled information only to provide its stated Notes-filtering and navigation-shortcut features, consistent with the Chrome Web Store User Data Policy and Limited Use requirements.

The developer does not receive this information through the extension. It is not sold, shared for advertising, used for credit or lending decisions, or made available for human review by the developer.

Retention and your controls

Temporary page-processing state is held while the content script is active. The two preferences remain until you change them, clear the extension's local storage or uninstall Margin. Chrome clears the extension's local storage when it is removed.

You can turn either setting off, revoke site access, disable Margin or uninstall it through Chrome. Refresh affected Substack tabs after disabling or uninstalling the extension to ensure any existing page modifications are cleared.

This privacy-policy website

This page has no forms, analytics, tracking scripts or third-party assets. It is hosted on GitHub Pages, which logs and stores visitors' IP addresses for security purposes, as described in GitHub's Pages documentation and GitHub's privacy statement. Visiting this website is separate from using the extension; Margin does not automatically contact this page.

Changes and contact

This policy will be updated if Margin's data handling changes. New data practices, if introduced, must be disclosed before they begin; this policy does not grant consent for undisclosed future tracking.

For privacy questions, use the developer contact or support channel shown on Margin's Chrome Web Store listing. Do not send passwords, account cookies or private feed screenshots when requesting support.