If you’re having an error in your site/app that says that is undefined is not a function and the error happens on the row containing .apply( matched.elem, args ); (jquery.js:4676 for version 2.0.3). You can do the following 2 things to figure out the error: 0. You need Chrome Dev Tools 1. Enable async for your dev… Continue reading jQuery error .apply( matched.elem, args ); undefined is not a function