I'm struggling to find a way to make a simple jquery call from within a label on Moodle 3.3 (using Boost theme). Any attempt to reference jquery via '$' or 'jquery' returns undefined. Could someone point me in the right direction?
regards,
Cathal.
Moodle loads Javascript (including jQuery) using AMD modules via RequireJS. This means that jQuery isn't available within the global namespace, only when you require it in another AMD module.
The developer wiki has a page introducing how to write Javascript modules in Moodle, including an example using jQuery.