The User Interface Editors are all organized in an hierarchical structure containing 4 levels. The top level is called a Tab. Beneath the tab, you can create one or more Groups. Beneath the groups you can create one or more Elements, which again can consist of one or more Fields.
Tabs
Groups
Elements
Fields
The structure is strict, meaning you cannot create a field directly to a flag or group. Fields can only be created to an element, which forces you to create a Tab, a Group and an Element before you can create the field you want.
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