6to4 tunnel
When searching with Google I often get a message that a 6to4 tunnel has been detected and that 6to4 is depracated and will be shut down. If I switch out of Firefox to AOL search or Edge my search with Google is not interrupted, so I presume the problem is with Firefox. Firefox is my default search engine and I want to keep it. Please fix this problem or tell me what to do to fix it. Before writing this message I went through an exhaustive test with Norton and found no other problems.
Wšě wotmołwy (1)
I think this problem is caused by older router firmware that doesn't support IPv6 addresses.
If your router has an update available, that would be the best approach: https://www.reddit.com/r/firefox/comments/hmc3t0/google_search_forcing_captcha_dialog_6to4_tunnel/
If not, you could try disabling Firefox from using IPv6 addresses:
(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.
(2) In the search box in the page, type or paste ipv and pause while the list is filtered
Experiment #1:
(3) Double-click the network.dns.ipv4OnlyDomains preference to display an editing field, and enter www.google.com (or your actual Google search site) then press Enter or click the blue check mark button to save the change.
You may need to clear cache to make sure Firefox requests a new address:
How to clear the Firefox cache (this should be limited to cache and not include cookies/history)
Experiment #2 (if #1 doesn't work):
(4) Double-click the network.dns.disableIPv6 preference to switch the value from false to true
(You may need to clear cache to make sure Firefox requests a new address)
Does that work?
More info on about:config: Configuration Editor for Firefox.