ultimate-woocomposer-backend.min.js 'multiple' FAIL :(


I upgraded my Wordpress site and my WooCommerce, and now I’ve a bit of problem:
WP version: 4.9.4
WooC version: 3.2.6

I use attributes for the products, but now the drop-down not works. When I open one of our products and I click on “Product data”, “Product short description” or anything else, nothing happens.

In the ChromeConsol i saw this:

  • ultimate-woocomposer-backend.min.js?ver=4.9.3:1 Uncaught Error: Option ‘multiple’ is not allowed for Select2 when attached to a element.
  • wp-auth-check.min.js?ver=4.9.3:1 Uncaught TypeError: Cannot read property ‘hasClass’ of undefined

I deactivated the “Ultimate Addons for Visual Composer” plugin, and after, everything works well.

My WPBakery version: 5.1