Today, all my WYSIWYG editors on the site lost visual tab and just show default buttons and text view.
Strange thing is, that only happened on local site, but on live site tinymce works normally, with several custom toolbars and dropdowns.
All plugins and settings on the sites are the same, and there are no js errors on either. I tried disabling all plugins that could mess with tinymce (e.g. Advanced Editor Tools) but nothing changed. Removed all my code from functions.php, also nothing changed. Live site still works, local site doesn’t:

I need ideas, where to look, what more can I check to find where’s the issue.