Sign-in stays put during background refreshes

Highlights

• · In beta.9 we calmed the sign-in flicker that showed up right after you log in. This release fixes the other half: during a routine background refresh of your sign-in (which happens every couple of hours), the title-bar indicator could briefly flip to 'Sign In' even though you were still signed in and your cloud features kept working normally. It now stays signed in, showing a brief 'Signing in...' only while the refresh finishes. If you ever see it drop to signed-out on its own again, please send a diagnostic report so we can confirm this one is fully closed.