I have a page that, when executing
apex.message.alert( "Test" );
will show

I have stripped the application of everything and have uploaded it to apex.oracle.com
When I create a new application and recreate the same page, I get what I was expecting:

I just cannot find what is causing the stripped application to show the OK button as it should be.
Has anybody seen this before and know how to solve it?
Workspace name : HUE_API
User name: FORUM_MEMBER
Password: Help_Jan_22
Application: 83706 - TEST (with faulty OK button)
Application: 90282 - TEST2 (with correct button display).