4.3: Collapse manual toggle example
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**Primary Actor**: User

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

**Goal**: Show user collapse with manual toggle example

Main success scenario:
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1. User opens Collapse demo page
2. User clicks on Manual toggle sub-menu
3. User see clickable "Show content" and "Hide content" buttons
4. User see div block with "Some content"
5. When user clicks on "Hide content", then "Some content" disappear
6. When user clicks on "Show content", then "Some content" appear

Variations:
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2*. User scrolls to Manual toggle sub-menu