scripts are being deferred somehow which is breaking parts of my site

Question

Today I noticed the blog section of my site was not rendering correctly, and the console was spitting out errors that I knew where to do with jquery not loading.

When I looked at source code all the scripts that where added by WordPress (wp_enqueue_script) had an extra element added to it, so: <script type='text/javascript' src='//code.jquery.com/jquery-2.2.0.min.js'></script>

become: <script type='text/javascript' src='//code.jquery.com/jquery-2.2.0.min.js' defer '></script>

so 'defer' and a single quote mark is being added.

I need these scripts to load in the , when I register the scripts I do set load in the footer as false.

I'm not sure why/how 'defer' is being added? Or why a single quote mark is also added? I'm also not sure if deferring them is what breaks the page or this rouge single quote mark?

I do use 'Autoptimize' but I have turned it off and cleared out all caches.

The only hack around it, short term, is to hardcode the scripts into the header.php and these are not deferred.

Answer 1

Our client had almost the same exact issue which was caused by a very outdated (and lazily written) plugin called ESB URL Extension that failed to account for a closing apostrophe.

Since our customer had quite a few active plugins on a live site (without staging options) I didn't want to start disabling things to locate the error. Instead, I installed the String Locator plugin (a great tool which I often use) and searched the plugin directory for occurrences of "defer" and was eventually able to identify the culprit.

Answer 2

Probably a (badly developed) plugin, disable plugins one by one until the defer attribute goes away. If not it could also be a theme thing, briefly switch to a default WordPress core theme to double-check?

frank