Pinned Tabs: should stay on the same pinned tab if only the subdomain changes

1. Pin www.google.com
2. In the Pinned Tab on www.google.com click on "Sign in"
3. A new Open Tabs opens because the domain has changed to accounts.google.com
4. After log in, it redirects back to www.google.com but now you are not in the Pinned Tab anymore, you are stuck in the Open Tabs.

#3 above should not happen while staying on the same main domain (google.com in this case), it makes pinning Gmail, Google Calendar difficult to use when they require login.

I suspect the problem is a bit more complicated than this, in theory there are equivalent domains that you may want to stay on in the same tab, or sites that use SSO for login where the SSO domain could be completely different.

0.99.130.2-beta

Sequoia (15)