If you use a VPN, you should be aware that Firefox and Chrome browsers for Windows use a technology that may put your privacy at risk.
This security hole may cause the real IP address leak, even when using a VPN. The detailed information about this security hole can be found in Github website here.
Here is what Github has to say about this security hole:
Since this security hole can affect many VPN users, we strongly recommend to read the following information, explaining how to overcome this issue by taking few simple steps:
Chrome for Windows. Google offers a fix titled ‘WebRTC Network Limiter‘. The tiny Chrome extension (just 7.31KB) disables the WebRTC multiple-routes option in Chrome’s privacy settings while configuring WebRTC not to use certain IP addresses.
After you install the extension, it is recommended to check if WebRTC has been disabled. In order to do that, you should visit Browserleaks website and see if the WebRTC is enabled or disabled.
Firefox for Windows. To disable WebRTC in Firefox for Windows, you have to take a few more steps. At first, you will need to type “about:config” into the URL bar and press Enter. Then look for “media.peerconnection.enabled” and double click to set it to “false”.
However, the best way to avoid the leaks is using NordVPN’s proxy extension for Chrome and Firefox. Not only does it replace your IP address for private browsing and encrypt your Internet data, it also blocks WebRTC leaks.