topic Re: Firefox should respect OS DNS configuration by default in Discussions

Firefox should respect OS DNS configuration by default

WildStar — Thu, 25 Jun 2026 13:31:15 GMT

Firefox used DNS over HTTPS to bypass my operating system's DNS settings and ignore my local DNS infrastructure. In a network using split-horizon DNS, this caused internal traffic to use the external/public IP address instead of the intended LAN address.

Browsers should respect the operating system's DNS configuration by default, or make it much more obvious when they choose not to.

Here's an example.

Microsoft Edge currently offers a "Use current service provider" option for secure DNS, which respects existing operating system and network DNS configurations. I believe Firefox should offer similar behavior by default.

Re: Firefox should respect OS DNS configuration by default - Status changed to: New idea

Jon — Fri, 26 Jun 2026 10:24:23 GMT

Thanks for submitting an idea to the Mozilla Connect community! Your idea is now open to votes (aka kudos) and comments.

Re: Firefox should respect OS DNS configuration by default

herman34 — Thu, 24 Sep 2026 12:47:12 GMT

I’ve run into this kind of issue with local DNS as well. If you’re using split-horizon DNS, having Firefox silently use its own DoH resolver can definitely cause problems because the browser ends up getting a completely different address from the one your local DNS server provides. I think the main issue is making the behaviour obvious. DoH is useful, but if Firefox is going to bypass the OS DNS settings, users should be able to see that clearly and choose whether they want it. An option similar to Edge’s “Use current service provider” would make sense for networks where the local DNS setup is intentional.