The cities from your iPhone's Clock app, on Safari's new tab instead: installed from the App Store, with the same clocks on your Mac and your iPhone.
The Safari-specific flow, start to finish.
A short tour of the widget. Already sold? Skip ahead.
The rich style borrows the idea of the Clock app on iPhone: a clock is light between 6:00 and 18:00 in its own zone and dark the rest of the time, so a row of faces shows at a glance who is at work and who is asleep. The cities are not read from the Clock app or iCloud. They are stored on your Start Page HQ account, which is why the same list appears in Safari on the Mac and the iPhone without an iCloud setting, and in Chrome or Firefox if you use those elsewhere.
Unlike Chrome and Firefox, Safari does not ship its own time zone data. It uses the one built into macOS and iOS, and Apple updates it through system updates. If a clock is off by an hour after a country changes its daylight saving rules, a pending macOS or iOS update is the likely fix, not a Safari one. On iPhone, Safari freezes tabs it moves to the background. Every clock reads the system time whenever it draws, so the faces are right the moment you return.

Pair the World Clock widget with these. One install gets you all of them.

Your local time, large, as the first thing on the tab.

Current conditions for the cities on your clocks.

The month at a glance, for trips across zones.

Days until the flight, next to the time where you land.

Pictures from the places your clocks are set to.

The dial-in number for the call in the other zone.
The World Clock widget is one of 50+ in Start Page HQ. Tasks, notes, RSS, AI tools, dev utilities — the same install gives you all of them. Start free with 8 widgets on a page, or lift every limit at $4/month, $24/year, or $48 lifetime.
No. The Clock app keeps its cities on the device and in iCloud, and Apple does not expose them to Safari extensions. You add the cities once in the widget, and they sync through your Start Page HQ account to every Mac, iPhone, and iPad you sign into.
Open the app once, then tick Start Page HQ under Safari → Settings → Extensions on the Mac. On iPhone or iPad, go to the Settings app → Safari → Extensions and turn it on with Allow.
The App Store app runs on macOS 12.4 or later and iOS 15 or later. One free download covers both, and the Safari extension is inside the app.
Safari takes time zone rules from macOS or iOS. When a country changes its rules, the fix arrives as a system update, so install any pending macOS or iOS update and the clock corrects itself.
Free plan, no credit card — see plans or try the demo without installing.