Get responsive breakpoint in Bootstrap 4 Beta

file.js

// Based on https://stackoverflow.com/a/37141090/4354249 (credit https://stackoverflow.com/users/4354249/farside)
// Bootstrap 4 beta has changed the classes - they use d-*-none instead of hidden-*-up.

function getResponsiveBreakpoint() {
    var envs = ["xs", "sm", "md", "lg", "xl"];
    var env = "";

    var $el = $("<div>");
    $el.appendTo($("body"));

    for (var i = envs.length - 1; i >= 0; i--) {
        env = envs[i];
        $el.addClass("d-" + env + "-none");
        if ($el.is(":hidden")) {
            break; // env detected
        }
    }
    $el.remove();
    return env;
}

thanks! that's true, they did update of classes names, again. Documentation can be found here: https://getbootstrap.com/docs/4.0/utilities/display/#hiding-elements

^_^ Thanks sergey