Unable to add menu items to menus on Ubuntu droplet

[znromonk]

This is a follow-up to #26047.

Although the bug has been reportedly closed, I am posting a bug report because there hasn't been an response in the support forums. This has caused my site to not be public due to the lack of a menu an the inability to add one.

My support forum post:

I tried a local installation of WordPress 4.3 on my Windows XAMPP server where everything ran smoothly. I tried adding a custom menu using the default twentyfifteen theme and it worked flawlessly.

I then followed nearly identical steps on my DigitalOcean Ubuntu droplet running PHP and MySQL and setup everything the same. But now I am not able to add anything to the custom menu. Every time I add anything (page/post/category/custom link) the message under Menu Structure changes from
Add menu items from the column on the left.
to
Drag each item into the order you prefer. Click the arrow on the right of the item to reveal additional configuration options.

I couldn't find any help online except a reference to a bug that was fixed in 3.8 #26047.. I can't understand why the same install works on my Windows XAMPP but not on the Ubuntu. This menu thing has been the only bug I have seen and have clean installed WordPress nearly 10 times.

I have tried repeated clean installs of Wordpress with and without any plugins.

[welcher]

Is this still relevant?