Board Thread:Support Requests - Getting Technical/@comment-33878615-20160910201000

On a wiki on which I’m an administrator, there’s a tab called “On the wiki.” I want to add a “Forum” link, which links to Special:Forum, to that tab.

It must be customizable, since on the wiki on which I’m an admin, it’s called “On the wiki,” whilst on this wiki (the Community Central), it’s called “On the Wiki.”

It’s not modifiable using MediaWiki:Wiki-navigation, so how do I add links to the tab? Do I have to use CSS? 