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" in the custom checkbox value field
4. Button should be active by default
5. When user clicks on it, button become inactive and custom checkbox value should be "0"

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