Question How do you disable DoH in Firefox?

[rashmi]

I thought of trying Firefox, but there is no option to disable DoH in Firefox. You can disable DoH in Chrome and Edge, but Firefox DOH (OFF) says "Use your default DNS." Chrome and Edge with DoH disabled don't leak DNS when I use VPN, but Firefox leaks DNS with DoH default and OFF.

 

[Bot]

You can disable DoH in Firefox. Go to Options > General > Network Settings > Settings, then under "Enable DNS over HTTPS", select "Off". If you're still experiencing DNS leaks, it might be an issue with your VPN configuration rather than Firefox itself.

 

[Spiff]

@Bot,
The Firefox DNS over HTTPS settings are not in Settings\ General\ Network Settings, but in Settings\ Privacy & Security\ DNS over HTTPS. That is where one can select "Off".
https://support.mozilla.org/en-US/kb/dns-over-https

 

[silversurfer]

I thought of trying Firefox, but there is no option to disable DoH in Firefox. You can disable DoH in Chrome and Edge, but Firefox DOH (OFF) says "Use your default DNS." Chrome and Edge with DoH disabled don't leak DNS when I use VPN, but Firefox leaks DNS with DoH default and OFF.

Sounds the issue for you is the DNS leak in Firefox while using VPN?

Just check for Firefox settings related to WebRTC:

Use these instructions if you wish to manually disable WebRTC:

1. Type "about:config" into the address bar and hit Enter.
2. Click the button "I accept the risk!".
3. Type media.peerconnection.enabled in the search bar. Only one entry should appear.
4. Double-click on the entry to change it to false.

To enable WebRTC again, change it back to "true".

WebRTC

Learn about what WebRTC is and how to keep it from exposing your IP.

mullvad.net

 

[rashmi]

Sounds the issue for you is the DNS leak in Firefox while using VPN?

Just check for Firefox settings related to WebRTC:

In Firefox about:config, I've already disabled WebRTC.

 

[rashmi]

People have also reported a DNS leak issue here.

Firefox has DNS leak security issue

When I was using a proxy to surf the Internet, to ensure my security, I checked the DNS leak status. When I use Firefox, the query results show that my DNS is leaked and the DNS is my real DNS. However, when I use Chrome to query, there is no DNS leak. This is a serious security issue. Please...

connect.mozilla.org

 

[lokamoka820]

To disable DoH in Firefox, follow these steps:

1. Open Firefox: Open the Firefox browser on your device.
2. Click the menu button: Click the three horizontal lines () at the top right corner of the browser window.
3. Select Options: Click on “Options” from the drop-down menu.
4. Go to Network Settings: In the Options window, click on the “Network Settings” tab.
5. Scroll down to Enable DNS over HTTPS: Scroll down to the “Enable DNS over HTTPS” option.
6. Uncheck the box: Uncheck the box next to “Enable DNS over HTTPS” to disable DoH.
7. Click OK: Click the “OK” button to save your changes.

Alternatively, you can also disable DoH by using the about:config page:

1. Type about:config in the address bar: Type “about:config” in the address bar and press Enter.
2. Search for network.dns.disablePrefetch: Search for the “network.dns.disablePrefetch” preference.
3. Double-click to toggle: Double-click on the preference to toggle it to “true”.

Note: Disabling DoH may affect the performance and security of your internet connection. It is recommended to only disable DoH if you have a specific reason to do so, such as using a custom DNS server or experiencing issues with DoH.

 

[Spiff]

@lokamoka820,
What is your source?
What you wrote is similar to Bot's reply, but it is not what is in the Mozilla Support article.
https://support.mozilla.org/en-US/kb/dns-over-https

 

[SpiderWeb]

Ah! Go type this into your Firefox address bar:

about:config

Then search for network.trr.mode and set the value to 5. Here is a Firefox document explaining the settings.

Here is a useful Firefox document of other parameters that you might want to check also:

https://wiki.mozilla.org/Trusted_Recursive_Resolver

Then check what resolvers your Firefox browser is using via this useful website:

dnscheck.tools - check your dns resolvers

A tool to test for DNS leaks, DNSSEC validation, and more

www.dnscheck.tools

 

[rashmi]

Then search for network.trr.mode and set the value to 5.

Firefox has already set network.trr.mode to 5.