0.5: Accordion Initially opened example
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**Primary Actor**: User

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

**Goal**: Show user initially opened items example in accordion functionality

Main success scenario:
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1. User open Accordion demo page
2. User click on Initially opened sub-menu
3. User able to click on each item of 3
4. Item with name "Initially expanded" should be opened by default and content inside should be visible
5. When user click on this item, it should be closed
6. When user reload page, then initially expanded item should be opened again

Variations:
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2*. User scroll to Initially opened sub-menu