@Johann Are you using Brave on a work computer? I’m having the same issue as you. I haven’t tried it at home yet, but this on a work laptop. I’m wondering if there are some GPOs that affect this. I looked at my registry settings for chrome (Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Google\Chrome) but didn’t see anything that would indicate the disabling of DOH. I’ll probably dig into it some more later.
I have now found the solution to the problem.
As soon as policies are defined (= managed PC), the flag does not appear. If you delete the policies, the flag ‘Secure DNS lookups’ will be displayed.
This affects Chromium as well as all Chromium based browsers (Brave, Chrome, Vivaldi, Slimjet, etc.).
Any particular policies as I deleted the Chrome ones I found on my domain joined machine, left over from when I used to use Chrome I think, and it made no difference?
If this is confirmed then there needs to be an extra flag to re-enable it regardless of what kind of PC it is.
A browser says it’s “managed by your organization” if system policies are controlling some browser settings.
Then DOH (DNS over HTTPS) is blocked. This limitation should be lifted in the future.