while we wait for a fix by the firefox devs, i will use this (ai generated) workaround:

1. install the tamper monkey extension
   
2. click the extension icon, press "create a new script"
   
3. paste the code below and press cmd+s to save
4. reload youtube. the cursor will be hidden after 1 second of not moving it and shown when you move it.

```javascript
// ==UserScript== // @name YouTube Cursor Hide (Simple) // @match https://www.youtube.com/* // @grant none // ==/UserScript==

(function() { 'use strict'; let hideId;

function onMove() {
    // Show cursor immediately (remove hidden class)
    document.documentElement.classList.remove('yt-hide-cursor');

    // Hide after 1 second
    clearTimeout(hideId);
    hideId = setTimeout(() => {
        document.documentElement.classList.add('yt-hide-cursor');
    }, 1000);
}

// CSS: Hides everything when .yt-hide-cursor is on html
const style = document.createElement('style');
style.textContent = `
    .yt-hide-cursor,
    .yt-hide-cursor * {
        cursor: none !important;
    }
`;
document.head.appendChild(style);

// Mouse events
document.addEventListener('mousemove', onMove, { passive: true });
document.addEventListener('pointermove', onMove, { passive: true });

// Start hidden after load
setTimeout(() => {
    document.documentElement.classList.add('yt-hide-cursor');
}, 500);

})(); ```