9.12: Popover Manual triggering example
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**Primary Actor**: User

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

**Goal**: Show user how to manually trigger the popover

Main success scenario:
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1. User opens Popover demo page
2. User clicks on Manual triggering sub-menu
3. User see 3 clickable buttons "Show", "Hide" and "Toggle" and text "Text has attached popover"
4. When user clicks on "Show", then popover-container appear  above the text
5. When user clicks on "Hide", then popover-container disappeared
6. When user clicks on "Toggle", then popover-container appear  above the text
7. When user clicks on "Toggle" again, then popover-container disappeared
8. Template src should be written with show, hide, toggle methods

Variations:
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2*. User scroll to Manual triggering sub-menu