Оставьте так!

fn main() {}

// SPDX-License-Identifier: MIT-0

// ==UserScript==
// @name        LOR-Russification
// @namespace   https://www.linux.org.ru/*
// @description LOR-Russification
// @include     https://www.linux.org.ru/*
// @version     1
// @grant       none
// ==/UserScript==

(function () {
  
window.addEventListener("load", function() {

var c={_:"ъ",a:"А",b:"Б",c:"Ц",d:"Д",e:"Е",f:"Ф",g:"Г",h:"Х",i:"И",j:"Й",k:"К",l:"Л",m:"М",n:"Н",o:"О",p:"П",q:"Я",r:"Р",s:"С",t:"Т",u:"У",v:"Ж",w:"В",x:"Ь",y:"Ы",z:"З",A:"а",B:"б",C:"ц",D:"д",E:"е",F:"ф",G:"г",H:"х",I:"и",J:"й",K:"к",L:"л",M:"м",N:"н",O:"о",P:"п",Q:"я",R:"р",S:"с",T:"т",U:"у",V:"ж",W:"в",X:"ь",Y:"ы",Z:"з",};
    var a = {};
    var b = [];
    document.querySelectorAll('a[itemprop="creator"], .sign_more a, #loginGreating a, table.head a, .nickname, .message-table s, .tag, .secondary, [class="btn btn-default"], [class="btn btn-selected"], #sitetitle, #ft-info, .msg-top-header, .grid-3-2, .navLink, em, .group, option').forEach(function(d) {
        b.push(d)
    });
    document.querySelectorAll(".sign, .sign_more, article .title, .message-table td, .tracker-last p, .tracker-src p").forEach(function(d) {
        for (var e = 0; e < d.childNodes.length; e++) {
            var f = d.childNodes[e];
            if (f.nodeType === 3) {
                b.push(f)
            }
        }
    });
    b.forEach(function(g) {
        var h = g.textContent;
        var e = "";
        if (a[h] != undefined) {
            g.textContent = a[h];
            return
        }
        for (var f = 0; f < h.length; f++) {
            var d = h[f];
            var j = c[d];
            if (j === undefined) {
                e += d
            } else {
                e += j
            }
        }
        g.textContent = e;
        a[h] = e
    })
});
})();