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HTML 60c8bf6adc29

Specify "time origin" computation The time origin, which is the epoch for all performance timeline APIs, was previously defined in This makes its computation explicit, without changing its current definition and behavior. Notably: * "time origin becomes an environment settings object algorithm, computed differently for windows vs. worker scopes. * The 4 places where this timestamp is set are creation of an about:blank browsing context, the beginning of navigation, the confirmation of an unload prompt, and the creation of a worker. * The timestamp is a "shared monotonic clock" value, which is defined in HR-TIME (and internally in ECMAScript). As part of this PR, also refactored unload prompts to return a result rather than rely on a somewhat hand-wavy "refused to allow" property. See and See also

Noam Rosenthal