Can't Drag and Drop Widgets in Appearance Panel – Debug Tool saying jQuery is not defined

When trying to control Widgets using Drag and Drop functionality – nothing happens. The screen I am referencing is Under Appearance > Widgets.

I suspected a javascript error, so I opened Chrome debugging console – there are 3 errors listed saying jQuery is not defined. For some reason – jQuery is not loading on this page – any ideas?

Additionally, when I turn on WP_DEBUG to true I get the a huge list of PHP Strict standards errors. Can someone confirm whether this could be related? (see screenshot)

I am using WP 3.8 with PHP 5.4.4 in a local environment with MAMP.


  • Alexander
    • DEV MAN’s Mascot


    If jQuery isn’t defined, it’s likely that you have a plugin or theme conflict.

    Those “strict standards” errors shouldn’t be a problem. PHP has made some changes in recent versions, but will continue to support the older syntax for a while. We’re incrementally working on updating to conform to this with newer plugin versions, but it won’t affect the functionality at all.

    Next, let’s test for conflicts in code actively running on the site. Can you try switching to a default theme temporarily like TwentyThirteen. Let me know if the jQuery loads with this theme. If so, we know there’s a conflict with the active theme.

    If that doesn’t make a difference, try disabling all your plugins one at a time. Try reloading the page each time you deactivate one. If it starts working, we’ll know the last plugin you toggled was causing a problem.

    Once we identify a conflict, we can look for a specific solution for it.

    Let me know how it goes!

    • WPMU DEV Initiate

    Hi There

    Thanks for the quick response.

    1. That’s good to know about the php errors.

    2. I activated TwentyThirteen and the problem still existed. Then I went through each plugin – deactivating the one at a time to get to the issue. As soon as I renamed the ‘wpmudev-updates’ folder to ‘xxxwpmudev-updates’ the problem disappeared. So it appears to be tis particular plugin.

    3. Next question is – where do we go form here, I definitely had the plugin updated?


  • Alexander
    • DEV MAN’s Mascot

    Hey, I’m sorry for the delay here.

    I’m not sure that’s the problem It’s working ok for me with the latest WPMU DEV Dashboard, and WordPress 3.8.1

    This is likely the result of a plugin that is registering a new widget, or adding widget controls to the widget page.

    Can you try another test, but instead deactivate all the plugins first? Add WPMU DEV Dashboard and you shouldn’t see this problem.

    Also, is this happening on all sub sites? Or just you main site? Might have to do with plugins that are network activated

    Best regards,

Thank NAME, for their help.

Let NAME know exactly why they deserved these points.

Gift a custom amount of points.