https://winworldpc.com/res/js/sluggifyUI.js

1var updatableSlug = true;
2/* jQuery because BS brings it in; trivial to remove */
3function sluggify(str) {
4    if (!str) {
5        return "";
6    }
7    /* we could check for the existence of a slug too */
8    return str.toLowerCase() /* no uppercase in slug */
9        .replace(/[^a-z0-9-]/g, "-") /* get rid of non-alphanumerics/hyphen */
10		.replace(/--+/g, "-") /* get rid of doubled up hyphens */
11        .replace(/-$/g, "") /* get rid of trailing hyphens */
12        .replace(/^-/g, "") /* and leading ones too */;
13}
14function updateSlugMaybe(source) {
15    if (updatableSlug) {
16        $("#slug").val(sluggify($(source).val()))
17    }
18}
19/* if the slug box has its own value entered, don't overwrite */
20function slugBlur(source) {
21    /* is the slug empty, or is the same as a sluggified name? if so, make it changeable */
22    var val = $(source).val();
23    updatableSlug = !val || (sluggify($("#name").val()) == val);
24}