KA voting script, this time without down-voting, hopefully for the KA extension.

better-ka-voting-v2.js

(function () {

/* ---- Definitions and fetching information ---- */
const EXTENSION_ITEM_CLASSNAME = "m-better-voting";

let oldWrap = document.querySelector(".voting-wrap .discussion-meta-controls").firstChild;

//No voting wrap means we're looking at a child account program or a tutorial/offical video or program, contest, etc
if (!oldWrap || !oldWrap.innerText.includes("Vote")) {
    return;
}

const unvotedClass =    "link_1uvuyao-o_O-computing_77ub1h";
const votedClass =      "link_1uvuyao-o_O-computing_1w8n1i8";

const attr = KAdefine.require("./javascript/scratchpads-package/scratchpad-ui.js").ScratchpadUI.scratchpad.attributes;
const cookie = KAdefine.require("./javascript/shared-package/cookies.js").readCookie("fkey"); //getCSRF()

let voted = oldWrap.innerText.includes("Voted Up"); //If we've voted

const orgVotes = attr.sumVotesIncremented - (voted ? 1 : 0); //Number of votes not counting ours



/* ---- Defining Custom Behavior ---- */
let newWrap = document.createElement("span");
newWrap.classList.add("voting-wrap");
newWrap.innerHTML = `
    <a class="${unvotedClass} ${EXTENSION_ITEM_CLASSNAME}" id="m-vote-button">
        <span id="m-vote-text">Vote Up</span> • <span id="m-vote-count">${orgVotes}</span>
    </a>
`;

const voteCount = newWrap.querySelector("#m-vote-count");
const voteButton = newWrap.querySelector("#m-vote-button");
const voteText = newWrap.querySelector("#m-vote-text");

function mVoteClick () {
    voted = !voted;

    mVoteUpdate();

    var req = new XMLHttpRequest();
    req.addEventListener("load", function () {
        if (this.status === 204) return; //204. No Content.
        var res = JSON.parse(this.response);
        if (res.error) {
            alert("Failed with error:\n\n" + res.error);
        }
    });
    //Send our vote
    req.open("POST", `https://www.khanacademy.org/api/internal/discussions/voteentity?entity_key=${attr.key}&vote_type=${voted ? 1 : 0}`);
    req.setRequestHeader("X-KA-FKey", cookie);
    req.send();
}

function mVoteUpdate () {
    voteText.innerText = voted ? "Voted Up!" : "Vote Up";

    voteCount.innerText = orgVotes + (voted ? 1 : 0);

    if (voted) {
        voteButton.classList.replace(unvotedClass, votedClass);
    }else {
        voteButton.classList.replace(votedClass, unvotedClass);
    }
}

newWrap.addEventListener("click", mVoteClick);
oldWrap.parentNode.insertBefore(newWrap, oldWrap);
oldWrap.parentNode.removeChild(oldWrap);
mVoteUpdate();

})("©Matthias");