6.7: Dropdowns Mark item as disabled example
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**Primary Actor**: User

**Scope**: Ngx-bootstrap DEMO / BS version 3&4

**Goal**: Show user example how to mark dropdown item as disabled

Main success scenario:
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1. User opens Dropdowns demo page
2. User clicks on Mark item as disabled sub-menu
3. User see clickable button "Button dropdown"
4. When user clicks on "Button dropdown", then dropdown opened and there are 3 items, first is disabled and other is enabled
5. When user clicks on the first item, nothing happens
6. When user clicks on the second item, then dropdown closes
7. When user clicks on "Button dropdown" again, then dropdown opened and there are 3 items in the same state as previous
8. When user clicks on the third item, then dropdown closes

Variations:
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2*. User scroll to Mark item as disabled sub-menu