Cookies
facturium does not set any cookies.
What this site actually uses
Instead of cookies, the invoice builder uses your browser's IndexedDB storage to save your business profile, clients, and invoices; a small localStorage flag to remember your chosen interface language and paper-size default; sessionStorage for a short-lived hand-off of your current draft during a language switch or an undo; and Cache Storage, via the app's offline service worker, to keep the builder's own files available without a network connection. All four are strictly necessary for the app to function the way you'd expect — without them, nothing you enter would be saved between visits, and the app wouldn't work offline.
Why there's no cookie banner
A consent banner is for storage that isn't required for the site to work — typically analytics or advertising cookies. facturium sets none of those in this version: no tracking cookies, no third-party cookies, no analytics. The only storage it uses is the strictly-necessary kind described above, so there's nothing to ask permission for.
Clearing this storage
You can remove everything facturium has stored at any time from your browser's site-data settings for this domain. Doing so deletes your saved invoices and clients from this device; export a backup first from Settings if you want to keep a copy.