IPvFoo is a Chrome/Firefox extension that adds an icon to indicate whether the current page was fetched using IPv4 or IPv6. When you click the icon, a pop-up appears, listing the IP address for each domain that served the page elements.
Everything is captured privately using the webRequest API, without creating any additional network traffic.
https://chrome.google.com/webstore/detail/ipvfoo/ecanpcehffngcegjmadlcijfolapggal
https://addons.mozilla.org/addon/ipvfoo/
https://microsoftedge.microsoft.com/addons/detail/ipvfoo/dphnkggpaicipkljebciobedeiaiofod
(You can also run the Chrome version on Edge, as they are identical.)
IPvFoo cannot be ported to Safari because the webRequest API does not report IP addresses. In theory, a Safari extension could do its own DNS lookups over HTTPS, but such behavior is beyond the scope of IPvFoo.
IPvFoo shares a common codebase for Chrome and Firefox, but manifest.json is browser specific.
Firefox shows this error when running the Chrome version:
There was an error during the temporary add-on installation.
background.service_worker is currently disabled. Add background.scripts.
Chrome shows this error when running the Firefox version:
'background.scripts' requires manifest version of 2 or lower.
'page_action' requires manifest version of 2 or lower.
The use_*_manifest.sh.bat scripts in the manifest directory may be used to switch between versions.
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