As you might have noticed, some icons are huge and others are tiny on the StackExchange HNQ page (aka the main page). Here's a userscript that fixes this issue:
// ==UserScript==
// @name StackExchange Hot Questions fix site icon size
// @version 1.0
// @match https://stackexchange.com/
// @grant none
// @run-at document-end
// ==/UserScript==
(function() {
'use strict';
[].forEach.call(document.querySelectorAll('.hot-question-site-icon span img'), function(img) {
img.src = img.src.replace('48','32');
});
})();