Hi Jakub
Thanks for the question.
I actually think that name-spacing a 3rd party library is the cause of issues, not the solution.
If no one namespaced the ‘select2’ JS library, only 1 library would be enqueued into the admin page and would solve lots of JS errors.
When the page has multiple libraries, this is where we run into issues.
I have included some new settings in ACF PRO which allow you to change the select2 library from v3 to v4 or even remove it completely from ACF.
http://www.advancedcustomfields.com/resources/acfsettings/
Thanks
E
