WireGuard + Unbound: DNS for WireGuard peers stops working after reboot

[TheHellSite]

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Describe the bug
When the bug occurs all WireGuard peers connected to my OPNsense can no longer resolve DNS requests.
Please note that WireGuard peers can still access websites if I call them with their IP.
Restarting Unbound immediately solves the issue.
My LAN / VLAN clients are not affected by this.

To Reproduce

1. Enable Unbound.
2. Setup WireGuard Road Warrior with "AllowedIPs = 0.0.0.0/0" in remote peer config.
3. Restart OPNsense or Reload WAN or Change name of any interface
4. See error

Expected behavior
A clear and concise description of what you expected to happen.

Screenshots
Unbound config.

Relevant log files
None available as I don't know which would be relevant.

Environment
OPNsense 21.1.4-amd64
FreeBSD 12.1-RELEASE-p15-HBSD
OpenSSL 1.1.1k 25 Mar 2021

[TheHellSite]

SOLVED: opnsense/core#4142 (comment)