Chromium 84 includes a user-visible DoH setting:

controlled by this feature flag.
The DOH settings should always be displayed, regardless of whether the flag 'Secure DNS' is set or whether the browser is managed.
We are seeing support requests for this feature now that it's available in Chrome 85 by default: https://twitter.com/Ginger__T/status/1313059566964400129
Is this just waiting on a design from @karenkliu?
We probably just want to copy the Chrome UI for this in brave://settings/security > advanced:

let's do what @diracdeltas suggested - probably don't need a design for this one
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We probably just want to copy the Chrome UI for this in brave://settings/security > advanced: