A number of my plugins, including event calendar, broke after updating to UUA Theme 1.1. I discovered it's because the 1.1 theme appears to use an old way of registering its jquery version, which then doesn't play nice with other WordPress functionality. It does it in this file: /home/uucpalou/public_html/wp-content/themes/uua-congregation/lib/scripts.php It's these 2 lines which are breaking everything: wp_deregister_script( 'jquery' );
wp_register_script( 'jquery', "//ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js", array(), '3.2.1' ); I commented out those 2 lines (which returns WordPress to using the default WordPress jquery) and everything worked again. Everything else seemed to continue to work with any new theme functionality. I'm not a jquery expert, but I found an article from way back in 2012 saying, "Don't do it this way" (which is how it was implemented in v1.1) and one from a few months ago saying, "Do it this way". Old: http://msyk.es/blog/prevent-jquery-wordpress-theme/
New: https://wpengine.com/support/including-a-different-jquery-version-in-wordpress/