fixed code

// Input data
let atxt = "WASD";
let acol = [9,13,10,4];
let bx = [0,-1,0,1];    // relative x offsets
let by = [5,6,7,6];     // relative y offsets
let shiftAmount = 1;    // how much to move right each loop
let maxLoops = 10;       // number of times to repeat the text
let loopDelay = 700;    // delay between loops in milliseconds

let currentLoop = 0;    // completed loops counter

// Calculate absolute positions based on cursor
let absBx = bx.map(x => x + cursor.x);
let absBy = by.map(y => y + cursor.y);

// Character check function
function ct(x, y, t, c) {
    if (!Tile.exists(Math.floor(x/20)*20, Math.floor(y/10)*10)) return false;
    let tile = Tile.get(Math.floor(x/20)*20, Math.floor(y/10)*10);
    if (!tile.done) return false;
    let info = getCharInfoXY(x, y);
    let sum = info.color + info.deco*248 + info.deco.italic*124 + info.deco.underline*62 + info.deco.strike*31;
    return info.char === t && sum === c;
}

// Paste a run of the text, skipping existing characters
function pasteRun(index = 0) {
    if (index >= atxt.length) {
        currentLoop++;
        if (currentLoop < maxLoops) {
            // Shift all x positions for the next run
            for (let i = 0; i < absBx.length; i++) absBx[i] += shiftAmount;
            // Schedule next run after a delay
            setTimeout(() => pasteRun(0), loopDelay);
        }
        return;
    }

    // Only write if the character is not already correct
    if (!ct(absBx[index], absBy[index], atxt[index], acol[index])) {
        writeCharAt(atxt[index], acol[index], absBx[index], absBy[index]);
    }

    // Next character in the run
    requestAnimationFrame(() => pasteRun(index + 1));
}

// Start looping autopaste
pasteRun();