When I search, I come up with a link, but the explorer itself appears to be missing! The info indicates the following. Note though, that there is NOTHING after the "The following objects are available....". No explorer. Is this a browser setting issue or something not tested in the new help site?
API Explorer
The following objects are available through the Workfront API.
Click an object to display all the information that can be accessed. For more detailed information about using the API Explorer, see Using the API Explorer .
Marty Gawry - CapabilitySource