Docs: clicking on Concurrency Primitives takes you directly to the first sub-section

[ScalaWilliam]

So you cannot get back to the root of this section - just odd behaviour.

Reproduction:

• Click Simple Examples
• Click Concurrency Primitives

Browser: Chrome on Windows.

Same issue on other sections, like here:

Regards,

[dohrisalim]

I'll start working on this issue