Opera and DNS over HTTPS

operaoperandi

operaoperandi

Question for the network experts: I have installed "DNS over HTTPS" (Quad9) in the form of a profile on my iMac Pro with the latest macOS Sonoma. When I call up the test page (on.quad9.net), Safari tells me "Yes, you are using Quad9", but Opera (latest version) tells me "No, you don't use Quad9". Why? The installed profile should apply system-wide in the network. Only when I activate DoH in the Opera settings and add Quad9 (again!) does it also work under Opera...
Can someone explain this to me?