Make Slack's <pre> <code> use Consolas font

slackmonofont.js

// ==UserScript==
// @name        Slack Better Motospace Font
// @namespace   slackmonofont
// @include     https://*.slack.com/*
// @version     1
// @grant       none
// ==/UserScript==

function addGlobalStyle(css) {
    var head, style;
    head = document.getElementsByTagName('head')[0];
    if (!head) { return; }
    style = document.createElement('style');
    style.type = 'text/css';
    style.innerHTML = css;
    head.appendChild(style);
}

addGlobalStyle('pre { font-family: Consolas, monospace !important; }');
addGlobalStyle('code { font-family: Consolas, monospace !important; }');