2.3: Buttons Custom checkbox value example
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**Primary Actor**: User

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

**Goal**: Show user button example with custom checkbox value

Main success scenario:
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1. User opens Buttons demo page
2. User clicks on Custom checkbox value sub-menu
3. User see 1 clickable button with text: "Single Toggle" and "1" putted in the custom checkbox value field above it
4. Button should be active by default with aria-pressed= "false"
5. When user clicks on the Single Toggle button, it becomes active and aria-pressed changed to "true". In the custom checkbox value shown "1"
5. When user clicks on it again, the Single Toggle button becomes inactive with aria-pressed= "false", and the custom checkbox value changed to "0"

Variations:
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2*. User scrolls to Custom checkbox value sub-menu