This page explains first-party cookies used by Ferrumium. The current implementation uses authentication cookies for signed-in sessions, security cookies for request protection, and a language preference cookie. It does not set first-party cookies for advertising or behavioral profiling.

Cookies

Ferrumium uses only first-party cookies that are needed to run the service. Authentication cookies keep signed-in sessions working and authorize account requests. They are kept for a limited period so you do not have to sign in on every page. Security cookies help protect forms and account actions from cross-site request forgery, and usually last only for the browser session.

Ferrumium also uses a language preference cookie so the interface can open in the language you selected on later visits. This preference is used for interface continuity, not for advertising or behavioral profiling, and is kept for about one year unless you change it or clear your browser data.

Browser Storage

Ferrumium uses browser storage to keep the app usable and consistent while you move between pages. Browser storage is different from cookies: it is not sent automatically with every HTTP request. The app reads it only when the interface needs it, such as when applying your theme, restoring planner settings, avoiding duplicate page-visit events, or remembering that you dismissed a banner.

When you are signed in, Ferrumium syncs account preferences and site choices through authenticated API requests so they can follow your account. This includes your visual theme, planner settings, performance settings, keyboard shortcuts, menu preferences, favorites, recent items, preferred recipes, workspace state for production planning and distribution trees, save map calibration, cookie banner dismissal, dismissed announcements, and wiki feedback choices. These are used for preference and interface continuity, not for advertising or behavioral profiling. They are kept until you change or reset the related setting, or until your account is deleted.

In guest mode or while signed out, Ferrumium does not store guest data on Ferrumium servers and does not sync it to an account. The browser may keep local interface preferences, guest mode state, guest onboarding state, workspace state, and dismissal choices on that device only. If you clear browser data, switch browsers, or use another device, that local guest data may be lost.

Ferrumium may also keep short-lived page state in the current browser tab, such as visit grouping, duplicate-event prevention, or temporary planner flow state. This is used for session continuity and is cleared automatically when the tab or browser session ends.