Problem with multiple "home" pages protected by shibboleth

[Rod Widdowson]

> I don’t think there is a solution, but could be wrong

I would concur (see "the web is hopelessly broken" passim).  

Consider, what you are wanting is for the tabs to share "state" (the fact
that you are logged in).  However you also requiring that that the tabs do
not share state during the login process, so you need to sacrifice one of
the requirements [*].  In my experience users learn pretty quickly to park
their sessions on the discovery page until the first log on has happened -
that way they actually do not have to do the login dance more than once,
with some careful spin you can make this into a feature.

Rod

[*] yea, I'm sure that you could imagine some compound system in which some
state was per tab (for instance a noisy URL), and some state per browser
(cookie).  I am no HTTP expert (thank goodness), but I'd guess that doing
that would sacrifice some other requirement.