Assert the page on screen has been open for at least a number of seconds, by the browser's own clock for the page (performance.now(), the time since the page began to load). It proves a wait in front of a protected form was long enough for the form's time limit.
Examples
Then the page should have been open for at least 2 seconds
And the page should have been open for at least 5 seconds
Then the page should have been open for at least 1 second
And the form should have been open for at least 6 seconds
Then the form should have been open for at least 3 seconds
Pattern
Then(/^the (?:page|form) should have been open for at least (\d+) seconds?$/, …)
Part of @webship-js/drupal-core-steps (github.com/webship/drupal-core-steps), a step pack for Webship-js 2.0.x.