I searched through the issue tracker and didn’t see anything about this. I don’t know if the docs site is currently defaulting to API 5.0, however both the default docs and the 5.0 docs seem to actually contain partially outdated information (i.e., I don’t know if it’s all outdated).
To give you an example of what I’m talking about, compare these docs for the EventSystem class:
(Default API level) Redirecting to latest version of com.unity.ugui
(Explicit 5.0 API level) Unity - Scripting API:
(Explicit 4.62 API level) Unity - Scripting API: EventSystem
Notice the member variables listed. The 4.62 docs page is what actually has the correct and up-to-date information. It’s worth noting that the offline documentation included with the Unity install also suffers from this issue.