Angular 4 Bootstrap dropdown require Popper.js

Question

I have a fresh created Angular 4 CLI app. After running this:

npm install bootstrap@4.0.0-beta jquery popper.js --save

and editing .angular

Answer 1

For Angular 8

npm install bootstrap jquery popper.js --save

     "styles": [
      "src/styles.scss",
      "node_modules/bootstrap/dist/css/bootstrap.min.css"
    ],
    "scripts": [
      "node_modules/jquery/dist/jquery.slim.min.js",
      "node_modules/popper.js/dist/umd/popper.min.js",
      "node_modules/bootstrap/dist/js/bootstrap.min.js"
    ],