Popover de bootstrap para angular

============= Agregar el popover de bootstrap para angular==========

web: https://ng-bootstrap.github.io/#/getting-started
install: npm install --save @ng-bootstrap/ng-bootstrap

add: import {NgbModule} from '@ng-bootstrap/ng-bootstrap';

@NgModule({
  ...
  imports: [NgbModule, ...],
  ...
})
export class YourAppModule {
}

example:
https://ng-bootstrap.github.io/#/components/popover/examples

<button type="button" class="btn btn-outline-secondary mr-2" placement="top"
        ngbPopover="Vivamus sagittis lacus vel augue laoreet rutrum faucibus." popoverTitle="Popover on top">
  Popover on top
</button>