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.
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Tabs
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Groups
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Elements
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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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