What are they and how do we use them?
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How we use cookies
Our system uses cookies to allow you to log into the site, and access restricted content and services.
| Name | Purpose | Expires |
|---|---|---|
| csrftoken | Allows the site to avoid Cross Site Request Forgery attacks. Its value is randomly generated every time a session is created. | A year. Note that this token does not identify the user in any way. |
| sessionid | Randoly generated value that identifies the logged-in user to allow accessing restricted content. | The soonest of: closing the browser window, 15 minutes of inactivity, or 8 hours. |
Last reviewed: 3 Jun 2026