The Chrome-specific flow, start to finish.
A short tour of the widget. Already sold? Skip ahead.
Chrome's tight integration with Google accounts is the easiest path for this widget: if you're already signed into Google in Chrome, the Connect flow opens the OAuth picker pre-populated with your accounts and a single click finishes setup. The Start Page HQ extension does not piggy-back on Chrome's signed-in identity automatically — you still go through Google's OAuth screen, but it takes one click instead of typing your password.
If you use Chrome profiles (work / personal), each profile is its own Chrome user and its own Start Page HQ install. Connect a different Google account in the Calendar widget on each profile — your work profile shows the work calendar, your personal profile shows your personal one. The accounts don't cross over even when both profiles are open at once.

Pair the Calendar widget with these. One install gets you all of them.
The Calendar widget is one of 50+ in Start Page HQ. Tasks, notes, RSS, AI tools, dev utilities — the same install gives you all of them. $25/year or $49 lifetime, no free tier.
Chrome being signed into Google doesn't automatically grant third-party extensions access to your data — that's a deliberate Chrome / Google security boundary. The OAuth flow is what gives the Calendar widget read access to your events, scoped to read-only and revocable from your Google account at any time.
Yes — and they stay separate. Each Chrome profile installs Start Page HQ independently and the Calendar widget connects to whichever Google account you authorise inside that profile. Your work profile can show the work calendar while your personal profile shows the personal one, even with both windows open simultaneously.
Yes. After connecting, you pick which calendar to display per widget instance — primary or any shared calendar your Google account can read. Pin two Calendar widgets on the same page (one per calendar) if you want both visible at once.
Not currently — the widget is read-only. Clicking an event opens it in Google Calendar in a new tab, which is where editing happens. Read-only also means the OAuth scope is narrower, which most users prefer.