The former takes people from other domains and makes their posts green text on green background. The colors are manually set and not reflective of any magazine styles or the like, but I have no idea why rgba(20, 45, 20, 1.0) is the color someone chose. I recommend anyone who wants that script edit line#41 to something like GM_addStyle('[data-is-federated-content="true"] { background-color: #EEE; }');, but even then this is a bit annoying to have to do manually.