Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Lolu chungechunge lwabekwa kunqolobane. Uyacelwa ubuze umbuzo omusha uma udinga usizo.

IPv6 Not working in Firefox!!!

  • 31 uphendule
  • 0 zinale nkinga
  • 1 view
  • Igcine ukuphendulwa ngu jonzn4SUSE

more options

Hi Everyone, IPv6 not working in Firefox, but in Google Chrome, Windows CMD, Microsoft Edge, and Opera is working fine, I'm using Cisco Secure Client as a VPN Client, and connect to the VPN IPv6 will enable and you can use IPv6 easily, but in Firefox only IPv4 working, and the problem only in Firefox

Hi Everyone, IPv6 not working in Firefox, but in Google Chrome, Windows CMD, Microsoft Edge, and Opera is working fine, I'm using Cisco Secure Client as a VPN Client, and connect to the VPN IPv6 will enable and you can use IPv6 easily, but in Firefox only IPv4 working, and the problem only in Firefox

All Replies (20)

more options

What is giving you the impression that IPv6 is not working? Show the issue. Are you trying to access a site(s) and it not working?

more options
more options

This forum site is a good example. I changed my network to IPv6 and couldn't access this site. see screenshot https://sitereport.netcraft.com/?url=http://support.mozilla.org

Okulungisiwe ngu jonzn4SUSE

more options

it's so easy, when Using Cisco Secure client just open https://ipv6test.google.com/ in Google Chrome, Opera, Microsoft Edge and any Chromium browser you will see you have IPv6, but when open the same website in Firefox you will you don't have IPv6 there is no need for screenshot, it's obvious

Okulungisiwe ngu AHMNco

more options

Does it still happen in a new profile? An easy way to test a new profile is to install Developer Edition and see if it happens there or refresh your existing profile. Make sure you stay signed out of your sync account when testing.

more options

I installed fresh version of Firefox Developer, still only IPv4 surprisingly with this behavior of Firefox I'm thinking to move to Chrome, however I do like Firefox but without IPv6 is too hard to use it, Firefox getting slower day by day and IPv6 is missing here

more options

This is a better test. https://test-ipv6.com/ What is your network setup? I have a router and then modem. I can make changes to my router and then only be on IPv6. I'll do that and post the results.

more options

I checked it seems Firefox blocking IPv6 Your browser has real working IPv6 address - but is avoiding using it. We're concerned about this. screenshot added Firefox with alert and Chrome is normal

more options

After making changes to my router and enabling IPv6 on it and my OS, my DHCP in now handing out IPv6 address and here is the test. see screenshots Your issue is not the browser, but network.

more options

Are you on VPN?

more options

I checked it seems Firefox blocking IPv6 I added screenshot as well

more options

AHMN48 said

I'm using Cisco Secure Client as a VPN Client, and connect to the VPN IPv6 will enable and you can use IPv6 easily, but in Firefox only IPv4 working, and the problem only in Firefox

you can see I mentioned at first

more options

Test off VPN. VPN issues are not my concern because we have no control over your VPN unless your using what provided by Mozilla.

more options

That may be a bug, something Dev will have to look into when it comes to Cisco Anyconnect VPN.

more options

This isn't VPN issue, If you check you will see Firefox blocking IPv6, but the same VPN working fine for Chrome, Edge, Opera, Windows and everything else, when Only Firefox has this issue so this isn't VPN problem, this is Firefox problem

more options

Again, nothing to be fixed here. Go open a bug and Dev will have to speak with Cisco to see where the issue is. It works off VPN, but your issue is while on VPN. Clearly a compatibility issue between the two vendors.

more options

I found the issue, Firefox blocking Virtual IPv6, Firefox only accepts real IPv6, since using VPN IPv6 is virtual then IPv6 block by Firefox by default, so in about:config is there any way to fix this issue? I want to use IPv6 and there is way for sure, but I don't know how Again this is not related to VPN

more options

Someone closer to Dev will chime in if there's a switch to flip in about:config. That's why I said open a bug and Dev will check.

more options

and how Can I open a bug report?

more options
  1. 1
  2. 2