How to update navigation links in MediaWiki

I usually do not post technical details here, but this one seems to be a fairly common issue and took an hour of my time, so here it is hoping it saves somebody else some time...

Changing the "navigation" (or sidebar) on MediaWiki in itself is in fact pretty straight forward - if you figure out the right way to do it, which is not easy due to confusing documentation.  So here's what you need to do:

1. Log into your MediaWiki as "Admin" or "Sysop".  If you're not sure what this means, see below.
2. Go to: .../index.php?title=MediaWiki:Sidebar - for example  http://www.example.com/wiki/index.php?title=MediaWiki:Sidebar
3. You will see the content of the sidebar, or navigation links, on a Wiki page as a list with a format of Link|name like this:

• navigation
• mainpage|mainpage
• portal-url|portal
• currentevents-url|currentevents
• ...

The rest is easy - edit this page like any other Wiki page, you will see the "unordered" list with "**" entries.  Add or modify as you wish.

For example, if you have a "To Do" page on your wiki and the page is called "To Do List" (meaning that its URL is .../index.php?title=To_Do_List), and you want to add it right after the link to Main Page, simply add this after the "mainpage" line:

** To Do List|To Do

Save and enjoy.

Now, the login as admin is important since this page (MediaWiki:Sidebar) is a special page and not editable by regular users, so if you do not login as admin you will not see the "edit" tab, and that will be confusing.  If this is a shared Wiki installation that somebody else has installed and you do not have admin access, you have to ask them to do the change.  If it's your Wiki but you do not remember the admin user name, go to Special:Listusers (.../index.php?title=Special:Listusers) and you will see whether you have Admin, Sysop, or something along those lines.  This is the name you specified at the time of installation.