6.6: Dropdowns Disabled menu example
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**Primary Actor**: User

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

**Goal**: Show user example how to use isDisabled property in dropdown

Main success scenario:
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1. User opens Dropdowns demo page
2. User clicks on Disabled menu sub-menu
3. User see 2 clickable buttons "Button dropdown" and "Enable/Disable"
4. When user clicks on "Button dropdown", then dropdown opened and there are 4 items, 1 of them is separated
5. When user clicks on any item, dropdown closes
6. When user clicks on "Enable/Disable", then "Button dropdown" disabled and user can't click on it
7. When user clicks on "Enable/Disable" again, then "Button dropdown" active again
8. When user clicks on "Button dropdown" again, then dropdown opened and there are 4 items
9. When user clicks on any item, dropdown closes

Variations:
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2*. User scroll to Disabled menu sub-menu