1. performanceobserver api

2. performanceobserverentrylist api

3. performanceobserverentrylist api: getentries

4. performanceobserverentrylist api: getentriesbyname

5. performanceobserverentrylist api: getentriesbytype

6. performanceobserver api: disconnect

7. performanceobserver api: observe

8. performanceobserver api: `performanceobserver()` constructor

9. performanceobserver api: `performanceobserver()` constructor: `droppedentriescount()` parameter

10. performanceobserver api: `supportedentrytypes()` static method

11. performanceobserver api: takerecords

12. performanceobserver api: available in workers