To clarify, the extension in ADS is like XEvent Profiler in Management Studio (which also is built using Extended Events). The name “SQL Server Profiler” is confusing, as this is not the same tool (UI) that’s been available since SQL Server 7.0.
To install the extension, click on it, and then select Install. Once it’s installed you can select Reload and it will move into the top half of the window under Enabled. Notice that when you select the extension, information about how to use it also appears.
Erin has a lot of useful information here, so check it out.