unbound Problem with Google Chrome

[akironet]

Hello everyone,
I have a special problem with a customer: an OPNsense is running as a firewall on a fixed IP address from Magenta in Vienna, Austria, the web server is operated in the internal LAN, NAT forwarding to the internal IP address has been set up, so you can access the web server from outside. In unbound I have set up a separate rule for each of the sub.domains.pages which also points back to the internal server (override). This worked without any problems until recently. Now, however, another subdomain has been added on an external server - *.domainname.com in unbound no longer works, so I had to enter all subdomains running on the internal server in unbound, the external subdomain is found via the public DNS.
On the Macs in the LAN everything still works if you use Safari or Firefox as a browser, but some colleagues prefer Google Chrome, where I always end up on the opesense when I call up the subdomains on the internal server, with a warning of an attempted rebind attack.
I have already found out that Chrome apparently uses an internal DNS system, but by default it is set to use the Mac's system settings anyway. Nevertheless it does not work.
Does anyone have any advice on what I could do?

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[zan]

Have you tried disabling "Use Secure DNS" in Chrome's security setting?
If Secure DNS is enabled Chrome will prioritize using DNS over HTTPS to its own DNS resolvers over network stack's DNS resolvers.