Offentligkonst.se has some functionality which relies on being given access to the users position. Some browsers, e.g. Chrome, blocks doing that if the website is not https.

The problem is that the server running offentligkonst.se runs an OS which is too old to support letsencrypt/certbot.

Offentligkonst.se is likely not the only thing running on that server meaning an upgrade/ migration needs to take more tools/services into account.