Borger.dk (Danish National e-ID & Government Services) Blocked by NextDNS Unless Block Page + CA Are Enabled

Description:

borger.dk is an essential Danish public-service domain and the entry point for MitID (the national MFA/identity system used across public and private organizations). When using NextDNS, Borgee.dk and MitID flows fail to load unless Block Page is enabled and the NextDNS CA certificate is installed.

This suggests that something in the current configuration causes the domain to be intercepted or blocked unless decrypted by the CA.

What I’ve tested:

• Issue reproduced by multiple independent users.
• Happens on different networks and devices.
• Disabling all privacy settings, blocklists, threat-intelligence lists, parental controls, and custom rules does not fix the issue.
• Only enabling Block Page + installing the NextDNS CA makes borger.dk and e-Boks work.

Expected behavior:

Borger.dk and related MitID login services should load normally without requiring the Block Page or the CA.

Actual behavior:

The site fails to load or breaks during the authentication flow unless Block Page + CA are enabled.

Domains involved (as far as observed):

• borger.dk (main site)
• digitalpost.dk
• post.borger.dk
• gateway.digitalpost.dk
• + various supporting subdomains during login