Custom Scrollbars in Firefox 63/64+

Customizable scrollbar for Gecko based browsers (Firefox).
Fai una domanda, pubblica una recensione, oppure segnala lo script.
/* ==UserStyle==
@name           Custom Scrollbars in Firefox 63/64+
@namespace      scrollbar-c-w
@version        1.0.3
@description    Customizable scrollbar for Gecko based browsers (Firefox).
@author         krystian3w
@license        CC-BY-SA-4.0 (https://creativecommons.org/licenses/by-sa/4.0/)
@preprocessor   less
@var color  bar              "bar"                                       #C1C1C1
@var color  bg               "background"                                #F1F1F1
@var select scrollbar-width  "width almost size"                         ["auto","thin","none"]
@var select scrollbar-select "width <select> size (may no longer works)" ["auto","thin","none"]
@var select inherit          "Change width all scrollbars"               {yes: "inherit", no: "auto"}
@var select simplebar        "Disable glitching with Simplebar?"         {yes: "none", no: "block"}

// @compatible   firefox Firefox
==/UserStyle== */
@-moz-document regexp("^(https?|moz-extension)\\:\\/\\/.*$") {
    &:root {
        scrollbar-face-color: @bar !important;
        scrollbar-track-color: @bg !important;

        scrollbar-color: @bar @bg !important;
        scrollbar-width: @scrollbar-width !important;
        * {
            scrollbar-width: @inherit !important;
        }
    }
    /* glitched on few firefox versions - may no longer needed */
    select {
        &:not([multiple]):not([size]) {
            scrollbar-width: @scrollbar-select !important;
        }
    }
    div[class*="simplebar-track"][style*="visible"] {
        display: @simplebar;
    }
}