Ensure PerformanceObserver callback fires for all observed entries between observe/disconnect calls. On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE". PerformanceObserver callback fired: 1 entries PASS mark1 PerformanceObserver callback fired: 2 entries PASS mark2 PASS mark3 PerformanceObserver callback fired: 1 entries PASS mark7 PASS successfullyParsed is true TEST COMPLETE