hypercal for Firefox does not collect, sell or share any data.
It only communicates with the hypercal instance you configured during set up.

What it stores
In the browser's local extension storage, on your device only:
- the address of your hypercal server and the app password you enter;
- your settings (reminder notifications on or off, the calendar quick add uses);
- a cached copy of your upcoming agenda and reminders, so the popup and sidebar open instantly.
Nothing is synced to other devices. Pressing Disconnect, or removing the extension, deletes it.

Where it connects
- Your own hypercal server, at the address you enter. It reads your agenda and reminders from there, and sends events you add with quick add or import. That server is run by you or your organisation, not by the extension's developers.
- A web site hosting an .ics file, only when you right-click a link to it and choose "Import into hypercal". It downloads that one file and sends it to your server. Firefox asks your permission for that site first.
It makes no other network requests: no analytics, no telemetry, no advertising, no third-party services.

Selected text
When you choose "Add ... to hypercal" on selected text, the text is read on your device and opens hypercal's event editor in a new tab. It is not saved until you save the event there.

Revoking access
Press Disconnect in the extension's settings, then revoke the app password in hypercal under Settings, Connectors, App passwords. Disconnecting alone leaves the password valid on the server.

Contact
contact-project+kreuz-com-group-hyper-calendar-84857751-issue-@incoming.gitlab.com