Bootstrap 4: Uncaught ReferenceError: Popper is not defined

I've installed Bootstrap 4 using Node and Gulp and when running the application I get the following error

Uncaught ReferenceError: Popper is not defined

I've only been using the Bootstrap grid system so far and I haven't used anything that would require the Bootstrap JS. Looks to me like Bootstrap is missing something or I haven't installed it correctly (to be honest it's probably me) - has anyone else come across the same issue or know a fix at all?


Since our Bootstrap beta 2 release, we added two new dist files : bootstrap.bundle.js and bootstrap.bundle.min.js which contain Popper.js inside

Plus use this link to find the latest release of Popper.js : because the above linked release (1.8.2) is very old, latest is 1.12.9

BTW you should choose the UMD release of Popper.js because it's the one used by Bootstrap