Drupal ckeditor IMCE upload button missing


Many custom themes conflict with the javascript from IMCE and the upload button doesn’t appear.

Download themekey module from d.o. (https://www.drupal.org/project/themekey) and enable it.

Then build a rule to use the admin theme on “imce” path like this:

drupal:path = imce -> Seven or in my case Shiny