I am having a strange difficulty with dropdowns on my installation of MDB. Most everything I have tested works fine. Collapsibles. Modals. Popovers. Carousel. I have not checked dropdowns in the navbar yet,  but the hamburger-pancakes properly unfolds on small screens. Though only using the locally hosted stylesheet instead of the CDN I notice. Using example dropdowns from your docs, the strange result is the following. Click on the dropdown. Nothing happens,  not even a click or hover  effect. Now hit the up-arrow key. The list of items appears free-floating near the root of the page. Like other plugins the dropdown is initialized with

$(function () { $('.dropdown-toggle').dropdown() })

Should I post my script stack and console messages? I see

Uncaught TypeError: Cannot read property 'addEventListener' of null(…)
Uncaught TypeError: $(...).sideNav is not a function(…)
Uncaught SyntaxError: Unexpected token |
jQuery.Deferred exception: Cannot read property 'init' of undefined TypeError: Cannot read property 'init' of undefined
    at HTMLDocument. (http://localhost:9000/:45:11)
    at j (http://localhost:9000/bower/MDBootstrap/js/jquery-3.2.1.min.js:2:29999)
    at k (http://localhost:9000/bower/MDBootstrap/js/jquery-3.2.1.min.js:2:30313) undefined
Uncaught TypeError: Cannot read property 'init' of undefined(…)
GET http://localhost:9000/mdb-addons/mdb-lightbox-ui.html 404 (Not Found)

Working with Harp JS. I have not tried SideNav yet.

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