ReadonlydurationReadonlyidReadonlyindexWhich visit of the frame it is: 1 on the first show, one more on every resume. The engine's bookkeeping and the tests read it; no preset and no recording field renders it.
ReadonlyleftReadonlynavReadonlyshownWhen the screen was shown — the engine's clock after the enter's burst, or the commit of a resume.
Readonlystarted
A visit that ended: what it was, how long it lasted by the engine's clock, measured to the moment the transition that ended it began (the tap or the edge), not to the commit after the covering screen's own burst, and when it was left — the moment the screen stopped being in front.