Kyle Maurer

When using WordPress multisite, the “My Sites” menu item will be added to the admin bar. Out of the box, this menu has a few limitations: 
1. It is as wide as the longest title of one of your sites. Lame. 
1. If your list of sites is too long, it will not fit on your screen and you can’t reach the bottom ones. Also lame. 
This plugin is an attempt to remedy these and other issues and make the My Sites menu as useful as possible for multiple-site admins.
What it does: 
1. If a user’s list of sites grows past a certain number, scrolling is enabled on the list. This way you can always reach every site. 
1. Site titles are truncated if they get too long so your menu isn’t crazy wide.
All in all, this is a very light plugin. How it works is it removes the existing My Sites menu and adds in this one plus the previously described functionality.

Better My Sites Menu

When using WordPress multisite, the "My Sites" menu item will be added to the admin bar. Out of the box, this menu has a few limitations:

kodeala

Reorder Multisite Sites Dropdown gives WordPress Multisite administrators a powerful tool to organize the My Sites dropdown in the WordPress Admin Bar. With this plugin, you can customize how sites appear in the admin bar so they are easier to find and better organized for your workflow. It is especially useful for WordPress Multisite networks with many sites where the default alphabetical ordering becomes difficult to manage, enhancing the existing WordPress multisite admin bar experience without modifying WordPress core functionality.
With this plugin, you can:
<ul>
<li>Reorder sites in the My Sites dropdown using drag-and-drop.</li>
<li>Manually set ordering using number input fields for quick repositioning.</li>
<li>Create groups to organize related sites together.</li>
<li>Add divider lines to visually separate sections.</li>
<li>Nest sites inside groups for better structure.</li>
</ul>
The ordering interface is available in the Network Admin under Settings > Reorder My Sites

Reorder Multisite Sites Dropdown

Adds advanced ordering controls to the WordPress Multisite My Sites admin bar dropdown, allowing administrators to organize sites with drag-and-drop,  …

Better My Sites Menu vs Reorder Multisite Sites Dropdown