I had Gmail pinned in one of my Orion window. It got logged-out for some reason. (Very unusual; not sure why that happened.) When I press the "Log in" button in the pinned tab, Orion opens a new tab for me to log in, rather than logging in in the existing tab.
More surprising, I can't get the pinned tab to the logged-in state. After I've logged in on the new tab, I tried a variety of ways to update the pinned one, but none work. Editing the URL of the pinned tab opens yet another new tab, rather than navigating the pinned one. So I'm stuck with the rigamarole of unpinning the dead tab, deleting it, pinning the new tab, and rearranging the pins so that they're in the right order again.
I should be able to navigate a pinned tab in order to perform routine operations like login, when necessary.
0.99.128.2.1-beta (WebKit 619.1.11.111.2)
Sonoma (14)