Before opening an issue, please search for duplicates (opened and closed)
https://github.com/valor-software/ngx-bootstrap/issues
There's no need to open an issue here if you want to ask general question, use [StackOverflow](https://stackoverflow.com/questions/tagged/ngx-bootstrap) or [Slack](https://ngx-slack.herokuapp.com/) instead

### Bug description or feature request:

### Plunker/StackBlitz that reproduces the issue:
Using Plunkr, StackBlitz is the best way to show your issue. Issues without link to an example of reproduction might be closed.

You can use one of starter templates:

Plunkr: https://plnkr.co/edit/0NipkZrnckZZROAcnjzB?p=preview

StackBlitz: https://stackblitz.com/edit/ngx-bootstrap?file=app%2Fapp.module.ts


### Versions of ngx-bootstrap, Angular, and Bootstrap:

ngx-bootstrap:

Angular:

Bootstrap:

### Build system: Angular CLI, System.js, webpack, starter seed:
