Title: this._addClass is not a function
Last modified: December 23, 2020

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# this._addClass is not a function

 *  Resolved [thepackagency](https://wordpress.org/support/users/thepackagency/)
 * (@thepackagency)
 * [5 years, 5 months ago](https://wordpress.org/support/topic/this-_addclass-is-not-a-function/)
 * When I’m on the WP DB admin page I get the following error: `slider.min.js:9 
   Uncaught TypeError: this._addClass is not a function
    at h.<computed>.<computed
   >._create (slider.min.js:9) at h.<computed>.<computed>.h.isFunction.a.<computed
   > [as _create] (widget.min.js:11) at h.<computed>.<computed>._createWidget (widget.
   min.js:11) at new h.<computed>.<computed> (widget.min.js:11) at HTMLDivElement.
   <anonymous> (widget.min.js:11) at Function.each (jquery.js:2) at n.fn.init.each(
   jquery.js:2) at n.fn.init.h.fn.<computed> [as slider] (widget.min.js:11) at HTMLDocument.
   <anonymous> (script.js:950) at i (jquery.js:2)`
 * And I can’t export a DB anymore..

Viewing 4 replies - 1 through 4 (of 4 total)

 *  Plugin Author [Delicious Brains](https://wordpress.org/support/users/deliciousbrains/)
 * (@deliciousbrains)
 * [5 years, 5 months ago](https://wordpress.org/support/topic/this-_addclass-is-not-a-function/#post-13840071)
 * This looks like the JavaScript from another plugin conflicting with our plugin.
   Have you got a Slider plugin running? The issue is coming from slider.min.js
 * You can try deactivating that plugin and trying the migration again, and sending
   the bug report to the slider plugin developer.
 *  Thread Starter [thepackagency](https://wordpress.org/support/users/thepackagency/)
 * (@thepackagency)
 * [5 years, 5 months ago](https://wordpress.org/support/topic/this-_addclass-is-not-a-function/#post-13840108)
 * This isn’t an plugin. Its a Wordpres/jQuery ui include: /wp-includes/js/jquery/
   ui/slider.min.js and it only shows on the admin page of WP DB migrate
 *  [cullylarson](https://wordpress.org/support/users/cullylarson/)
 * (@cullylarson)
 * [5 years, 4 months ago](https://wordpress.org/support/topic/this-_addclass-is-not-a-function/#post-13993650)
 * I’m having the same issue since upgrading to WordPress 5.6. When I click on any
   of the MigrateDB settings tabs I get this error and the tab doesn’t load. Pro
   version.
 *  [cullylarson](https://wordpress.org/support/users/cullylarson/)
 * (@cullylarson)
 * [5 years, 4 months ago](https://wordpress.org/support/topic/this-_addclass-is-not-a-function/#post-13999115)
 * I figured out my issue was actually with another plugin. Once that was fixed,
   the error in the Migrate DB area went away. To anyone else having this issue:
   try deactivating all plugins other than Migrate DB and see if it resolves the
   issue. If it does, reactivate plugins until you see the issue again. That should
   tell you which plugin is causing the problem.

Viewing 4 replies - 1 through 4 (of 4 total)

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## Tags

 * [jquery](https://wordpress.org/support/topic-tag/jquery/)

 * 4 replies
 * 3 participants
 * Last reply from: [cullylarson](https://wordpress.org/support/users/cullylarson/)
 * Last activity: [5 years, 4 months ago](https://wordpress.org/support/topic/this-_addclass-is-not-a-function/#post-13999115)
 * Status: resolved