15.12: Tooltip Custom class example
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**Primary Actor**: User

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

**Goal**: Show user how make tooltips with custom classes

Main success scenario:
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1. User opens Tooltip demo page
2. User clicks on Custom class sub-menu
3. User see button "Demo with custom class"
4. When user hover on "Demo with custom class", then tooltip-container appear above the button with specific style
5. When user move mouse out of the "Demo with custom class", then tooltip-container disappeared
6. Template src should be written with containerClass="customClass"

Variations:
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2*. User scroll to Custom class sub-menu