Dropdowns are toggleable, contextual overlays for displaying lists of links and more. They're made interactive with the included Bootstrap dropdown JavaScript plugin. They're toggled by clicking, not by hovering; this is [an intentional design decision.](http://markdotto.com/2012/02/27/bootstrap-explained-dropdowns/)
-Dropdowns are built on a third party library, [Popper.js](https://popper.js.org), which provides dynamic positioning and viewport detection. Be sure to include [popper.min.js](https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.3/umd/popper.min.js) before Bootstrap's JavaScript.
+Dropdowns are built on a third party library, [Popper.js](https://popper.js.org), which provides dynamic positioning and viewport detection. Be sure to include [popper.min.js]({{ site.cdn.popper }}) before Bootstrap's JavaScript.
If you're building our JS from source, it [requires `util.js`]({{ site.baseurl }}/docs/{{ site.docs_version }}/getting-started/javascript/#util).
Things to know when using the popover plugin:
-- Popovers rely on the 3rd party library [Popper.js](https://popper.js.org) for positioning. You must include [popper.min.js](https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.3/umd/popper.min.js) before bootstrap.js in order for popovers to work!
+- Popovers rely on the 3rd party library [Popper.js](https://popper.js.org) for positioning. You must include [popper.min.js]({{ site.cdn.popper }}) before bootstrap.js in order for popovers to work!
- Popovers require the [tooltip plugin]({{ site.baseurl }}/docs/{{ site.docs_version }}/components/tooltips/) as a dependency.
- If building our JS from source, it [requires `util.js`]({{ site.baseurl }}/docs/{{ site.docs_version }}/getting-started/javascript/#util).
- Popovers are opt-in for performance reasons, so **you must initialize them yourself**.
Things to know when using the tooltip plugin:
-- Tooltips rely on the 3rd party library [Popper.js](https://popper.js.org) for positioning. You must include [popper.min.js](https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.3/umd/popper.min.js) before bootstrap.js in order for tooltips to work!
+- Tooltips rely on the 3rd party library [Popper.js](https://popper.js.org) for positioning. You must include [popper.min.js]({{ site.cdn.popper }}) before bootstrap.js in order for tooltips to work!
- If building our JS from source, it [requires `util.js`]({{ site.baseurl }}/docs/{{ site.docs_version }}/getting-started/javascript/#util).
- Tooltips are opt-in for performance reasons, so **you must initialize them yourself**.
- Tooltips with zero-length titles are never displayed.