9.13: Popover Trigger by isOpen property example
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**Primary Actor**: User

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

**Goal**: Show user how to trigger the popover by isOpen property

Main success scenario:
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1. User opens Popover demo page
2. User clicks on Trigger by isOpen property sub-menu
3. User see clickable button "Toggle" and text "Text has attached popover"
4. When user clicks on "Toggle", then popover-container appear  above the text
5. When user clicks on "Toggle" again, then popover-container disappeared
6. Template src should be written with isOpen property

Variations:
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2*. User scroll to Trigger by isOpen property sub-menu