That's what I get for not testing this properly.
I have reverted both updates to the Essence theme and the Summernote editor plugin.
When updated, things should go back to "normal".
I'll try to attend to this better when I have more time. Thanks for catching the weird update in less than 24 hours!
WonderCMS has really had an amazing journey since 2008, and it's becoming more feature complete with plugins/themes.
Next release should be pretty exciting with a lot of improvements, including unlimited sub-menus.
Also, you have now been added to our list of contributors: https://www.wondercms.com/contributors
Thanks again for contributing, I'm sure we'll figure this out. To many more years of WonderCMS-ing!