mediasessionfixer.user.js

// ==UserScript==
// @name         mediasession fixer
// @version      2026-01-22
// @description  fixes my everlasting "missing artist metadata" issue in spotify
// @author       Alyxia
// @match        https://open.spotify.com/*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=spotify.com
// @grant        none
// ==/UserScript==

const __FIXER__ = window.__FIXER__ = {};
const FULL_SELECTOR = 'ul[aria-label="Now playing"] [data-encore-id="listRowSubtitle"] > * > :has([href])';
const NOW_PLAYING_SELECTOR = 'ul[aria-label="Now playing"]';
const ARTIST_TEXT_SELECTOR = '[data-encore-id="listRowSubtitle"] > * > :has([href])';

(async function() {
    'use strict';
    console.log('fixer: init');
    while (!(__FIXER__.target = document.querySelector(NOW_PLAYING_SELECTOR))) {
        console.log('fixer: waiting');
        await new Promise(resolve => setTimeout(resolve, 100));
    }
    console.log('fixer: done');

    // target = document.querySelector('ul[aria-label="Now playing"]');
    __FIXER__.observer = new MutationObserver((list) => {
        // console.log('handling\n', list);
        for (const rec of list) {
            if (rec.type === 'childList') {
                if (
                    // This is the previous track being removed
                    !!(Array.from(rec.removedNodes).length) ||
                    // This is a record for the addition of the new track before the old one was removed.
                    // The addedNodes entry here is not fully initialized
                    !!rec.previousSibling
                ) continue;
                // This is the play/pause button being switched out in the now playing cover art
                else if (!!(Array.from(rec.target.classList.values().filter(v => v.match('-button__'))).length)) {
                    console.log('fixer: handling presumed play/pause');
                    if (!(__FIXER__.currentArtist = document.querySelector(FULL_SELECTOR))) {
                        console.log('fixer: play/pause triggered but no current artist found?')
                    }

                    if (__FIXER__.currentArtist.innerText && !navigator.mediaSession.metadata.artist) {
                        navigator.mediaSession.metadata.artist = __FIXER__.currentArtist.innerText;
                        console.log('fixer: MEDIASESSION SET!', navigator.mediaSession.metadata);
                    }
                    return;
                }
                else {
                    console.log('fixer: handling presumed new song');
                    if (!(__FIXER__.newTrack = Array.from(rec.addedNodes)[0])) {
                        console.warn('fixer: new track started but no track node?')
                    }

                    let artistEl = __FIXER__.newTrack.querySelector('[data-encore-id="listRowSubtitle"] > * > :has([href])');
                    console.log('fixer: artistEl found', artistEl);
                    if (artistEl.innerText) {
                        navigator.mediaSession.metadata.artist = artistEl.innerText;
                        console.log('fixer: MEDIASESSION SET!', navigator.mediaSession.metadata);
                    }
                    return;
                }
            }
        }
        console.log('\n\n')
    });

    __FIXER__.observer.observe(__FIXER__.target, { childList: true, subtree: true });
})();