feat(mb_ui): replace atisket lookup with a synthetic Harmony Lookup external link (#1049)

- include one supported Harmony provider, MB Release ID and GTIN if it's
present. This allows to preselect the current Release in Harmony
(instead of lookup) as well as to ensure the widest lookup possible with
a barcode.
- render a single syntetic external link instead of Harmony lookup
button next to all supported provider URLs to reduce visual noise. It's
not very important which provider to use as soon as all of them provide
the same release.
- deprioritise beatport provider (because it's broken, so it will
short-circuit to GTIN), Apple Music/Itunes provider (because it supplies
less complete data compared to other providers), and Bandcamp (because
it often doesn't have the barcode, so it isn't participating in
syndicated releases in the idiomatic way). If none other providers are
found on the release, it will fall back to Bandcamp/Apple Music/Beatport
nevertheless.
- replace atisket entirely because it is on its way out and Harmony can
already do everything atisket was doing (and more).

<img width="333" height="795" alt="image"
src="https://github.com/user-attachments/assets/f72e3bcc-f4db-426b-a062-32ecbb9368f3"
/>

Author: arsinclair

mb_ui_enhancements.user.js

@@ -1,7 +1,7 @@
 // ==UserScript==
 // @name         Musicbrainz UI enhancements
 // @description  Various UI enhancements for Musicbrainz
-// @version      2026.7.23.1
+// @version      2026.8.25.1
 // @downloadURL  https://raw.githubusercontent.com/murdos/musicbrainz-userscripts/master/mb_ui_enhancements.user.js
 // @updateURL    https://raw.githubusercontent.com/murdos/musicbrainz-userscripts/master/mb_ui_enhancements.user.js
 // @icon         http://wiki.musicbrainz.org/images/3/3d/Musicbrainz_logo.png
@@ -16,6 +16,7 @@
 // @resource     errorIcon https://raw.githubusercontent.com/murdos/musicbrainz-userscripts/master/assets/icons/error.svg?v=2026.2.12.3
 // @resource     searchIcon https://raw.githubusercontent.com/murdos/musicbrainz-userscripts/master/assets/icons/search.svg?v=2026.2.12.3
 // @resource     searchArtistIcon https://raw.githubusercontent.com/murdos/musicbrainz-userscripts/master/assets/icons/search-artist.svg?v=2026.2.12.3
+// @resource     harmonyIcon https://harmony.pulsewidth.org.uk/favicon.svg?v=2026.8.25.3
 // @grant        GM_getResourceURL
 // @grant        GM_registerMenuCommand
 // @grant        GM_getValue
@@ -621,37 +622,47 @@ $(document).ready(function () {
         }
     }
 
-    // Display a-tisket links next to Deezer, Spotify, iTunes and Apple Music links
-    if (window.location.href.match(releaseRegex)) {
-        document.querySelectorAll('div#bottom-credits a').forEach(function (link) {
-            if (link.href.match(/deezer.com|(music|itunes).apple.com|spotify.com/)) {
-                let id;
-                let fragment;
-                let country;
-                if (link.href.match(/deezer.com/)) {
-                    id = new URL(link.href).pathname.split('/').slice(-1)[0];
-                    fragment = 'deez';
-                    country = 'GB%2CUS%2CIN';
-                } else if (link.href.match(/apple.com/)) {
-                    id = new URL(link.href).pathname.split('/', 5).slice(-1)[0].replace('id', '');
-                    fragment = 'itu';
-                    country = new URL(link.href).pathname.split('/', 2)[1];
-                } else if (link.href.match(/spotify.com/)) {
-                    id = new URL(link.href).pathname.split('/', 5).slice(-1)[0];
-                    fragment = 'spf';
-                    country = 'GB%2CUS%2CIN';
-                }
-
-                let next = link.nextElementSibling.nextElementSibling;
-                let newlink = document.createElement('a');
-                newlink.href = `https://atisket.pulsewidth.org.uk/?preferred_countries=${country}&${fragment}_id=${id}&preferred_vendor=${fragment}`;
-                newlink.text = 'a-tisket';
-
-                next.before(document.createTextNode(' ['));
-                next.before(newlink);
-                next.before(document.createTextNode(']'));
-            }
-        });
+    // Display a Harmony lookup link when the release has a supported provider URL
+    const releaseMatch = window.location.href.match(releaseRegex);
+    if (releaseMatch) {
+        const harmonyProviderHostname =
+            /^(?:[^.]+\.bandcamp\.com|www\.beatport\.com|music\.bugs\.co\.kr|(?:www\.)?deezer\.com|www\.discogs\.com|(?:geo\.)?(?:itunes|music)\.apple\.com|(?:www|m2)\.melon\.com|mora\.jp|ototoy\.jp|(?:play|www|open)\.qobuz\.com|open\.spotify\.com|(?:(?:www|listen)\.)?tidal\.com)$/i;
+        const barcode = document.querySelector('#sidebar dd.barcode')?.textContent.trim();
+        const validGtin =
+            barcode && /^(?:\d{8}|\d{12,14})$/.test(barcode)
+                ? barcode
+                      .split('')
+                      .reduce((checksum, digit, index) => checksum + Number(digit) * ((barcode.length - index) % 2 ? 1 : 3), 0) %
+                      10 ===
+                  0
+                : false;
+        const externalLinks = document.querySelector('#sidebar h2.external-links + ul.external_links');
+
+        const supportedProviderUrls = Array.from(externalLinks?.querySelectorAll('li a[href]') ?? [])
+            .map(link => new URL(link.href))
+            .filter(url => harmonyProviderHostname.test(url.hostname));
+        const lowerPriorityHostname = /^(?:[^.]+\.bandcamp\.com|www\.beatport\.com|(?:geo\.)?(?:itunes|music)\.apple\.com)$/i;
+        const providerUrl = supportedProviderUrls.find(url => !lowerPriorityHostname.test(url.hostname)) ?? supportedProviderUrls[0];
+
+        if (providerUrl) {
+            const harmonyUrl = new URL('https://harmony.pulsewidth.org.uk/release');
+            harmonyUrl.searchParams.set('url', providerUrl.href);
+            harmonyUrl.searchParams.set('category', 'preferred');
+            harmonyUrl.searchParams.set('musicbrainz', releaseMatch[1]);
+            if (validGtin) harmonyUrl.searchParams.set('gtin', barcode);
+
+            const harmonyLink = document.createElement('a');
+            harmonyLink.href = harmonyUrl.href;
+            harmonyLink.target = '_blank';
+            harmonyLink.rel = 'noopener';
+            harmonyLink.textContent = 'Lookup with Harmony';
+
+            const harmonyItem = document.createElement('li');
+            harmonyItem.style.backgroundImage = `url("${GM_getResourceURL('harmonyIcon')}")`;
+            harmonyItem.style.backgroundSize = '16px 16px';
+            harmonyItem.appendChild(harmonyLink);
+            externalLinks.appendChild(harmonyItem);
+        }
     }
 
     // Discogs link rollover