The time zone name and the UTC offset this browser is using right now. Nothing is uploaded.
The name is an IANA zone, such as Asia/Shanghai. The offset is for this moment, so daylight saving is already included. It is a setting of this browser, not a city lookup. The timezone converter turns one wall clock into another.
The zone and the offset are read in this tab. They are not uploaded.
Not where daylight saving moves the clock. The offset shown is for right now.
No. A zone such as Asia/Shanghai is a clock setting. This page does not look up a city.
It turns one wall-clock time into another zone. This page only names the zone this tab is using.
No. The name and the offset stay in this tab.
Not by itself. The zone follows the clock setting of this device, not the network address.