A top-tab switch inside the screen in front (SERP Top → Accounts): the top
chain entry becomes screen in place — the same ordinal, source and enter
time, the resume time of the switch — and no ordinal is taken (Android 451:
CompositeSerpTabbedFragment:serp_top:4 becomes …:serp_users:4 with a
later resume time). Outside a session, or with an empty chain, only the
front screen changes. The surface trail is not extended: whether a top-tab
switch is a new surface visit is not known.
A top-tab switch inside the screen in front (SERP Top → Accounts): the top chain entry becomes
screenin place — the same ordinal, source and enter time, the resume time of the switch — and no ordinal is taken (Android 451:CompositeSerpTabbedFragment:serp_top:4becomes…:serp_users:4with a later resume time). Outside a session, or with an empty chain, only the front screen changes. The surface trail is not extended: whether a top-tab switch is a new surface visit is not known.