Discord forces you to have two very large bars which are pretty much useless. A channel list and a members list. I just want chat. Ctrl+shift+I will open Dev Tools. You'll see a warning that 11/10, this is hacking you. It's not, but do your own due dilligence. Paste this and your two side bars will be much smaller.
// general flow: Select all div elements with a class. Step through each element.
// Check if class name contains relevant string.
// if so, set the width to "100px"
document.querySelectorAll('div[class]').forEach(function(elm){
if (-1 < elm.className.indexOf('sidebar')) {
elm.style['width']="100px";
}
if (-1 < elm.className.indexOf('membersWrap')) {
elm.style['width']="100px";
elm.style["min-width"]="50px";
}
})