From 1ae96590afb894a9ba7a07730db43cbf66515078 Mon Sep 17 00:00:00 2001
From: Jonathan Hunt <git@huntdesign.co.nz>
Date: Sat, 23 May 2026 10:18:28 +1200
Subject: [PATCH 1/9] #75 Return OpenSeadragon viewer object

---
 js/openseadragon_viewer.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/js/openseadragon_viewer.js b/js/openseadragon_viewer.js
index f6d6fb0..7883887 100644
--- a/js/openseadragon_viewer.js
+++ b/js/openseadragon_viewer.js
@@ -124,5 +124,6 @@
             });
         }
 
+        return viewer;
     };
 })(once);

From 51ec570ac575265edc129f8e7031eaaddadadc35 Mon Sep 17 00:00:00 2001
From: Jonathan Hunt <git@huntdesign.co.nz>
Date: Sat, 23 May 2026 10:55:35 +1200
Subject: [PATCH 2/9] #66 Initial commit of bookmark-url as submodule

---
 .../js/drupal-openseadragon-bookmark-url.js   |  43 +++++++
 .../js/openseadragon-bookmark-url.js          | 112 ++++++++++++++++++
 .../openseadragon_bookmark_url.info.yml       |   7 ++
 .../openseadragon_bookmark_url.libraries.yml  |   9 ++
 .../openseadragon_bookmark_url.module         |  17 +++
 5 files changed, 188 insertions(+)
 create mode 100644 modules/openseadragon_bookmark_url/js/drupal-openseadragon-bookmark-url.js
 create mode 100644 modules/openseadragon_bookmark_url/js/openseadragon-bookmark-url.js
 create mode 100644 modules/openseadragon_bookmark_url/openseadragon_bookmark_url.info.yml
 create mode 100644 modules/openseadragon_bookmark_url/openseadragon_bookmark_url.libraries.yml
 create mode 100644 modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module

diff --git a/modules/openseadragon_bookmark_url/js/drupal-openseadragon-bookmark-url.js b/modules/openseadragon_bookmark_url/js/drupal-openseadragon-bookmark-url.js
new file mode 100644
index 0000000..75ff66b
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/js/drupal-openseadragon-bookmark-url.js
@@ -0,0 +1,43 @@
+/*jslint browser: true*/
+/*global OpenSeadragon, Drupal*/
+/**
+ * @file
+ * Attaches openseadragon-bookmark-url to OpenSeadragon viewer.
+ */
+(function($, Drupal, drupalSettings, once) {
+  'use strict';
+
+  /**
+   * The DOM element that represents the Singleton Instance of this class.
+   * @type {string}
+   */
+  var base = '#openseadragon-viewer';
+
+  /**
+   * Invoke bookmark url and log any viewer changes in URL.
+   */
+  Drupal.behaviors.openSeadragonBookmarkURL = {
+    attach: function(context, settings) {
+      Object.keys(settings.openseadragon).forEach(function(osdViewerId) {
+        // Use custom element #id if set.
+        base = '#' + osdViewerId;
+        once('openSeadragonViewerBookmarkURL', base, context).forEach(function () {
+          Drupal.openSeadragonViewer[base].addHandler('bookmark-url-change', displayNewUrl);
+          Drupal.openSeadragonViewer[base].bookmarkUrl();
+        });
+      });
+    },
+    detach: function(context, settings, trigger) {
+      Object.keys(settings.openseadragon).forEach(function(osdViewerId) {
+        // Use custom element #id if set.
+        base = '#' + osdViewerId;
+        Drupal.openSeadragonViewer[base].removeHandler('bookmark-url-change', displayNewUrl);
+      });
+    }
+  };
+
+  function displayNewUrl(event) {
+    console.log('New URL:', event.url);
+  }
+
+})($, Drupal, drupalSettings, once);
diff --git a/modules/openseadragon_bookmark_url/js/openseadragon-bookmark-url.js b/modules/openseadragon_bookmark_url/js/openseadragon-bookmark-url.js
new file mode 100644
index 0000000..a611942
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/js/openseadragon-bookmark-url.js
@@ -0,0 +1,112 @@
+// OpenSeadragon Bookmark URL plugin 0.0.4
+
+(function() {
+
+  var $ = window.OpenSeadragon;
+
+  if (!$) {
+    $ = require('openseadragon');
+    if (!$) {
+      throw new Error('OpenSeadragon is missing.');
+    }
+  }
+
+  // ----------
+  $.Viewer.prototype.bookmarkUrl = function(options) {
+    options = options || {};
+    var trackPage = options.trackPage || false;
+
+    var self = this;
+
+    var updateTimeout;
+
+    var parseHash = function() {
+      var params = {};
+      var hash = window.location.hash.replace(/^#/, '');
+      if (hash) {
+        var parts = hash.split('&');
+        parts.forEach(function(part) {
+          var subparts = part.split('=');
+          var key = subparts[0];
+          var value = parseFloat(subparts[1]);
+          if (!key || isNaN(value)) {
+            console.error('bad hash param', part);
+          } else {
+            params[key] = value;
+          }
+        });
+      }
+
+      return params;
+    };
+
+    var updateUrl = function() {
+      // We only update once it's settled, so we're not constantly flashing the URL.
+      clearTimeout(updateTimeout);
+      updateTimeout = setTimeout(function() {
+        var zoom = self.viewport.getZoom();
+        var pan = self.viewport.getCenter();
+        var page = self.currentPage();
+        var oldUrl = location.pathname + location.hash;
+        var search = location.search;
+        var url = location.pathname + search + '#zoom=' + zoom + '&x=' + pan.x + '&y=' + pan.y;
+        if (trackPage) {
+          url = url + '&page=' + page;
+        }
+        history.replaceState({}, '', url);
+
+        if (url !== oldUrl) {
+          self.raiseEvent('bookmark-url-change', { url: location.href });
+        }
+      }, 100);
+    };
+
+    var useParams = function(params) {
+      var zoom = self.viewport.getZoom();
+      var pan = self.viewport.getCenter();
+      var page = self.currentPage();
+
+      if (trackPage && params.page !== undefined && params.page !== page) {
+        self.goToPage(params.page);
+        self.addOnceHandler('open', function() {
+          if (params.zoom !== undefined) {
+            self.viewport.zoomTo(params.zoom, null, true);
+          }
+          if (params.x !== undefined && params.y !== undefined && (params.x !== pan.x || params.y !== pan.y)) {
+            self.viewport.panTo(new $.Point(params.x, params.y), true);
+          }
+        });
+      } else {
+        if (params.zoom !== undefined && params.zoom !== zoom) {
+          self.viewport.zoomTo(params.zoom, null, true);
+        }
+        if (params.x !== undefined && params.y !== undefined && (params.x !== pan.x || params.y !== pan.y)) {
+          self.viewport.panTo(new $.Point(params.x, params.y), true);
+        }
+      }
+    };
+
+    var params = parseHash();
+
+    if (this.world.getItemCount() === 0) {
+      this.addOnceHandler('open', function() {
+        useParams(params);
+      });
+    } else {
+      useParams(params);
+    }
+
+    this.addHandler('zoom', updateUrl);
+    this.addHandler('pan', updateUrl);
+    if (trackPage) {
+      this.addHandler('page', updateUrl);
+    }
+
+    // Note that out own replaceState calls don't trigger hashchange events, so this is only if
+    // the user has modified the URL (by pasting one in, for instance).
+    window.addEventListener('hashchange', function() {
+      useParams(parseHash());
+    }, false);
+  };
+
+})();
diff --git a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.info.yml b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.info.yml
new file mode 100644
index 0000000..98a4ddd
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.info.yml
@@ -0,0 +1,7 @@
+name: 'OpenSeadragon Bookmark URL'
+type: module
+description: 'Wrapper for https://github.com/openseadragon/bookmark-url library'
+package: Media
+core_version_requirement: ^10 || ^11
+dependencies:
+  - openseadragon:openseadragon
diff --git a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.libraries.yml b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.libraries.yml
new file mode 100644
index 0000000..10d7b17
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.libraries.yml
@@ -0,0 +1,9 @@
+openseadragon_bookmark_url:
+  js:
+    js/drupal-openseadragon-bookmark-url.js: {}
+    js/openseadragon-bookmark-url.js: {}
+  dependencies:
+    - core/drupal
+    - core/once
+    - core/drupalSettings
+    - openseadragon/openseadragon
diff --git a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
new file mode 100644
index 0000000..d300e10
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
@@ -0,0 +1,17 @@
+<?php
+
+/**
+ * @file
+ * Attach bookmark-url.js.
+ */
+
+/**
+ * Attach openseadragon-bookmark-url.js to all pages.
+ *
+ * @todo: It would be good to target this better?
+ *
+ * {@inheritDoc}
+ */
+function openseadragon_bookmark_url_page_attachments(array &$page) {
+  $page['#attached']['library'][] = 'openseadragon_bookmark_url/openseadragon_bookmark_url';
+}

From ffa0b67db4ebb87b2d049e6e8be350d93462d358 Mon Sep 17 00:00:00 2001
From: Jonathan Hunt <git@huntdesign.co.nz>
Date: Sat, 23 May 2026 11:38:39 +1200
Subject: [PATCH 3/9] #66 Improve code style

---
 .../openseadragon_bookmark_url.module                           | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
index d300e10..7fa7ea4 100644
--- a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
+++ b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
@@ -8,7 +8,7 @@
 /**
  * Attach openseadragon-bookmark-url.js to all pages.
  *
- * @todo: It would be good to target this better?
+ * @todo: It would be good to target this better, e.g. load only when OSD is loaded.
  *
  * {@inheritDoc}
  */

From a1a05b46e7020cd651be47dbb78e9f18eb3cd839 Mon Sep 17 00:00:00 2001
From: Jonathan Hunt <git@huntdesign.co.nz>
Date: Sat, 23 May 2026 11:54:37 +1200
Subject: [PATCH 4/9] #66 Improve code style

---
 .../openseadragon_bookmark_url.module                           | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
index 7fa7ea4..644a77f 100644
--- a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
+++ b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
@@ -8,7 +8,7 @@
 /**
  * Attach openseadragon-bookmark-url.js to all pages.
  *
- * @todo: It would be good to target this better, e.g. load only when OSD is loaded.
+ * @todo It would be good to target this better, e.g. load only when OSD is loaded.
  *
  * {@inheritDoc}
  */

From 6d99755277b2376892cc51c88abc70ba88fdbf4f Mon Sep 17 00:00:00 2001
From: Jonathan Hunt <git@huntdesign.co.nz>
Date: Mon, 25 May 2026 10:49:43 +1200
Subject: [PATCH 5/9] #66 Remove local openseadragon-bookmark-url.js in favour
 of CDN

---
 .../js/drupal-openseadragon-bookmark-url.js   |  14 +--
 .../js/openseadragon-bookmark-url.js          | 112 ------------------
 .../openseadragon_bookmark_url.libraries.yml  |  16 ++-
 3 files changed, 16 insertions(+), 126 deletions(-)
 delete mode 100644 modules/openseadragon_bookmark_url/js/openseadragon-bookmark-url.js

diff --git a/modules/openseadragon_bookmark_url/js/drupal-openseadragon-bookmark-url.js b/modules/openseadragon_bookmark_url/js/drupal-openseadragon-bookmark-url.js
index 75ff66b..1f618b7 100644
--- a/modules/openseadragon_bookmark_url/js/drupal-openseadragon-bookmark-url.js
+++ b/modules/openseadragon_bookmark_url/js/drupal-openseadragon-bookmark-url.js
@@ -14,7 +14,7 @@
   var base = '#openseadragon-viewer';
 
   /**
-   * Invoke bookmark url and log any viewer changes in URL.
+   * Invoke bookmark url plugin.
    */
   Drupal.behaviors.openSeadragonBookmarkURL = {
     attach: function(context, settings) {
@@ -22,22 +22,10 @@
         // Use custom element #id if set.
         base = '#' + osdViewerId;
         once('openSeadragonViewerBookmarkURL', base, context).forEach(function () {
-          Drupal.openSeadragonViewer[base].addHandler('bookmark-url-change', displayNewUrl);
           Drupal.openSeadragonViewer[base].bookmarkUrl();
         });
       });
-    },
-    detach: function(context, settings, trigger) {
-      Object.keys(settings.openseadragon).forEach(function(osdViewerId) {
-        // Use custom element #id if set.
-        base = '#' + osdViewerId;
-        Drupal.openSeadragonViewer[base].removeHandler('bookmark-url-change', displayNewUrl);
-      });
     }
   };
 
-  function displayNewUrl(event) {
-    console.log('New URL:', event.url);
-  }
-
 })($, Drupal, drupalSettings, once);
diff --git a/modules/openseadragon_bookmark_url/js/openseadragon-bookmark-url.js b/modules/openseadragon_bookmark_url/js/openseadragon-bookmark-url.js
deleted file mode 100644
index a611942..0000000
--- a/modules/openseadragon_bookmark_url/js/openseadragon-bookmark-url.js
+++ /dev/null
@@ -1,112 +0,0 @@
-// OpenSeadragon Bookmark URL plugin 0.0.4
-
-(function() {
-
-  var $ = window.OpenSeadragon;
-
-  if (!$) {
-    $ = require('openseadragon');
-    if (!$) {
-      throw new Error('OpenSeadragon is missing.');
-    }
-  }
-
-  // ----------
-  $.Viewer.prototype.bookmarkUrl = function(options) {
-    options = options || {};
-    var trackPage = options.trackPage || false;
-
-    var self = this;
-
-    var updateTimeout;
-
-    var parseHash = function() {
-      var params = {};
-      var hash = window.location.hash.replace(/^#/, '');
-      if (hash) {
-        var parts = hash.split('&');
-        parts.forEach(function(part) {
-          var subparts = part.split('=');
-          var key = subparts[0];
-          var value = parseFloat(subparts[1]);
-          if (!key || isNaN(value)) {
-            console.error('bad hash param', part);
-          } else {
-            params[key] = value;
-          }
-        });
-      }
-
-      return params;
-    };
-
-    var updateUrl = function() {
-      // We only update once it's settled, so we're not constantly flashing the URL.
-      clearTimeout(updateTimeout);
-      updateTimeout = setTimeout(function() {
-        var zoom = self.viewport.getZoom();
-        var pan = self.viewport.getCenter();
-        var page = self.currentPage();
-        var oldUrl = location.pathname + location.hash;
-        var search = location.search;
-        var url = location.pathname + search + '#zoom=' + zoom + '&x=' + pan.x + '&y=' + pan.y;
-        if (trackPage) {
-          url = url + '&page=' + page;
-        }
-        history.replaceState({}, '', url);
-
-        if (url !== oldUrl) {
-          self.raiseEvent('bookmark-url-change', { url: location.href });
-        }
-      }, 100);
-    };
-
-    var useParams = function(params) {
-      var zoom = self.viewport.getZoom();
-      var pan = self.viewport.getCenter();
-      var page = self.currentPage();
-
-      if (trackPage && params.page !== undefined && params.page !== page) {
-        self.goToPage(params.page);
-        self.addOnceHandler('open', function() {
-          if (params.zoom !== undefined) {
-            self.viewport.zoomTo(params.zoom, null, true);
-          }
-          if (params.x !== undefined && params.y !== undefined && (params.x !== pan.x || params.y !== pan.y)) {
-            self.viewport.panTo(new $.Point(params.x, params.y), true);
-          }
-        });
-      } else {
-        if (params.zoom !== undefined && params.zoom !== zoom) {
-          self.viewport.zoomTo(params.zoom, null, true);
-        }
-        if (params.x !== undefined && params.y !== undefined && (params.x !== pan.x || params.y !== pan.y)) {
-          self.viewport.panTo(new $.Point(params.x, params.y), true);
-        }
-      }
-    };
-
-    var params = parseHash();
-
-    if (this.world.getItemCount() === 0) {
-      this.addOnceHandler('open', function() {
-        useParams(params);
-      });
-    } else {
-      useParams(params);
-    }
-
-    this.addHandler('zoom', updateUrl);
-    this.addHandler('pan', updateUrl);
-    if (trackPage) {
-      this.addHandler('page', updateUrl);
-    }
-
-    // Note that out own replaceState calls don't trigger hashchange events, so this is only if
-    // the user has modified the URL (by pasting one in, for instance).
-    window.addEventListener('hashchange', function() {
-      useParams(parseHash());
-    }, false);
-  };
-
-})();
diff --git a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.libraries.yml b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.libraries.yml
index 10d7b17..ce22ba3 100644
--- a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.libraries.yml
+++ b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.libraries.yml
@@ -1,9 +1,23 @@
+plugin:
+  remote: https://github.com/openseadragon/bookmark-url
+  version: "0.0.5"
+  license:
+    name: BSD-3-Clause
+    url: https://github.com/openseadragon/bookmark-url/blob/master/LICENSE
+    gpl-compatible: true
+  js:
+    https://cdn.jsdelivr.net/gh/openseadragon/bookmark-url@13c534c6ad7078fa44675f23185b75ee760d659c/openseadragon-bookmark-url.js:
+      type: external
+      minified: false
+      attributes:
+        integrity: "sha256-RDZWd2DzG9Asb3Pf3U0UrC0wKEGVJaC3D00Z9mqN63w="
+        crossorigin: anonymous
 openseadragon_bookmark_url:
   js:
     js/drupal-openseadragon-bookmark-url.js: {}
-    js/openseadragon-bookmark-url.js: {}
   dependencies:
     - core/drupal
     - core/once
     - core/drupalSettings
     - openseadragon/openseadragon
+    - openseadragon_bookmark_url/plugin

From 510339cf657a42dc15fe2e34d29e8a6c6933f0e9 Mon Sep 17 00:00:00 2001
From: Jonathan Hunt <git@huntdesign.co.nz>
Date: Mon, 25 May 2026 16:51:18 +1200
Subject: [PATCH 6/9] #66 Load openseadragon_bookmark_url js when
 openseadragon_formatter is used

---
 .../openseadragon_bookmark_url.module              | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
index 644a77f..f74eb9c 100644
--- a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
+++ b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
@@ -6,12 +6,18 @@
  */
 
 /**
- * Attach openseadragon-bookmark-url.js to all pages.
+ * Attach openseadragon_bookmark_url js if openseadragon_formatter used.
  *
- * @todo It would be good to target this better, e.g. load only when OSD is loaded.
+ * Implements hook_preprocess_HOOK().
  *
  * {@inheritDoc}
  */
-function openseadragon_bookmark_url_page_attachments(array &$page) {
-  $page['#attached']['library'][] = 'openseadragon_bookmark_url/openseadragon_bookmark_url';
+function openseadragon_bookmark_url_preprocess_field(&$variables) {
+  if (isset($variables['items'])) {
+    foreach ($variables['items'] as $item) {
+      if (isset($item['content']['#theme']) && $item['content']['#theme'] == 'openseadragon_formatter') {
+        $variables['#attached']['library'][] =  'openseadragon_bookmark_url/openseadragon_bookmark_url';
+      }
+    }
+  }
 }

From 158788273d60c7a854efc077b524b121e34f3e26 Mon Sep 17 00:00:00 2001
From: Jonathan Hunt <git@huntdesign.co.nz>
Date: Tue, 26 May 2026 08:43:27 +1200
Subject: [PATCH 7/9] #66 Improve code style

---
 .../openseadragon_bookmark_url.module                           | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
index f74eb9c..78b7351 100644
--- a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
+++ b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
@@ -16,7 +16,7 @@ function openseadragon_bookmark_url_preprocess_field(&$variables) {
   if (isset($variables['items'])) {
     foreach ($variables['items'] as $item) {
       if (isset($item['content']['#theme']) && $item['content']['#theme'] == 'openseadragon_formatter') {
-        $variables['#attached']['library'][] =  'openseadragon_bookmark_url/openseadragon_bookmark_url';
+        $variables['#attached']['library'][] = 'openseadragon_bookmark_url/openseadragon_bookmark_url';
       }
     }
   }

From be89e9aeedf892fae854d4dbf8b50785aa0348e8 Mon Sep 17 00:00:00 2001
From: Jonathan Hunt <git@huntdesign.co.nz>
Date: Tue, 26 May 2026 11:55:21 +1200
Subject: [PATCH 8/9] #66 Add README. Add configuration for media type and
 bookmark url field

---
 modules/openseadragon_bookmark_url/README.md  | 21 +++++++
 .../openseadragon_bookmark_url.settings.yml   |  5 ++
 .../openseadragon_bookmark_url.schema.yml     | 22 +++++++
 .../js/drupal-openseadragon-bookmark-url.js   | 13 +++-
 .../openseadragon_bookmark_url.module         | 15 +++++
 .../openseadragon_bookmark_url.services.yml   |  5 ++
 .../src/BookmarkUrlConfig.php                 | 61 +++++++++++++++++++
 7 files changed, 141 insertions(+), 1 deletion(-)
 create mode 100644 modules/openseadragon_bookmark_url/README.md
 create mode 100644 modules/openseadragon_bookmark_url/config/install/openseadragon_bookmark_url.settings.yml
 create mode 100644 modules/openseadragon_bookmark_url/config/schema/openseadragon_bookmark_url.schema.yml
 create mode 100644 modules/openseadragon_bookmark_url/openseadragon_bookmark_url.services.yml
 create mode 100644 modules/openseadragon_bookmark_url/src/BookmarkUrlConfig.php

diff --git a/modules/openseadragon_bookmark_url/README.md b/modules/openseadragon_bookmark_url/README.md
new file mode 100644
index 0000000..7876f96
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/README.md
@@ -0,0 +1,21 @@
+# OpenSeadragon Bookmark URL
+
+Enables the OpenSeadragon Bookmark URL plugin that tracks OpenSeadragon zoom level and coordinates to allow sharing of a display via URL.
+
+This module assumes you have added a string field to a media type that can hold the bookmark fragment, e.g.
+`file` with `field_bookmark_url`.
+
+## Requirements
+- [OpenSeadragon](https://www.drupal.org/project/openseadragon)
+
+## Installation
+
+Install as you would normally install a contributed Drupal module. For further information, see
+[Installing Drupal Modules](https://www.drupal.org/docs/extending-drupal/installing-modules).
+
+## Configuration
+Currently, no UI exists for configuration.
+
+Create an openseadragon_bookmark_url.settings.yml file and set `bookmark_url_bundle` to the media type, e.g. `file`, and `bookmark_url_field` to the field. The value from the specific media and field are inject into the Drupal settings available to javascript.
+* `bookmark_url_bundle`: `file`
+* `bookmark_url_field`: `field_bookmark_url`
diff --git a/modules/openseadragon_bookmark_url/config/install/openseadragon_bookmark_url.settings.yml b/modules/openseadragon_bookmark_url/config/install/openseadragon_bookmark_url.settings.yml
new file mode 100644
index 0000000..774f308
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/config/install/openseadragon_bookmark_url.settings.yml
@@ -0,0 +1,5 @@
+# Default configuration for the OpenSeadragon Bookmark URL submodule.
+# These values are intentionally empty; an administrator must choose the
+# appropriate content type and field for their site via the settings form.
+bookmark_url_bundle: ''
+bookmark_url_field: ''
diff --git a/modules/openseadragon_bookmark_url/config/schema/openseadragon_bookmark_url.schema.yml b/modules/openseadragon_bookmark_url/config/schema/openseadragon_bookmark_url.schema.yml
new file mode 100644
index 0000000..8cc8d2a
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/config/schema/openseadragon_bookmark_url.schema.yml
@@ -0,0 +1,22 @@
+# Schema for openseadragon_bookmark_url.settings config object.
+
+openseadragon_bookmark_url.settings:
+  type: config_object
+  label: 'OpenSeadragon Bookmark URL settings'
+  mapping:
+    bookmark_url_bundle:
+      type: string
+      label: 'Content type (bundle) machine name'
+      constraints:
+        # Must be a valid (media) bundle machine name or empty string.
+        Regex:
+          pattern: '/^[a-z0-9_]*$/'
+          message: 'The bundle must be a valid machine name (lowercase letters, digits, and underscores only).'
+
+    bookmark_url_field:
+      type: string
+      label: 'Field machine name that stores the bookmark URL'
+      constraints:
+        Regex:
+          pattern: '/^[a-z0-9_]*$/'
+          message: 'The field name must be a valid machine name (lowercase letters, digits, and underscores only).'
diff --git a/modules/openseadragon_bookmark_url/js/drupal-openseadragon-bookmark-url.js b/modules/openseadragon_bookmark_url/js/drupal-openseadragon-bookmark-url.js
index 1f618b7..ed1986c 100644
--- a/modules/openseadragon_bookmark_url/js/drupal-openseadragon-bookmark-url.js
+++ b/modules/openseadragon_bookmark_url/js/drupal-openseadragon-bookmark-url.js
@@ -22,7 +22,18 @@
         // Use custom element #id if set.
         base = '#' + osdViewerId;
         once('openSeadragonViewerBookmarkURL', base, context).forEach(function () {
-          Drupal.openSeadragonViewer[base].bookmarkUrl();
+          // Load bookmark url, but without page tracking, to allow hash to be set.
+          Drupal.openSeadragonViewer[base].bookmarkUrl({trackPage: false});
+          if (window.location.hash === '') {
+            var hash =  settings.openseadragon[osdViewerId].openseadragonBookmarkUrl;
+            if (hash !== '') {
+              window.location.hash = hash;
+            }
+          }
+          // With hash set or not, once OSD loaded, begin page tracking.
+          Drupal.openSeadragonViewer[base].addOnceHandler('open', function(){
+            Drupal.openSeadragonViewer[base].bookmarkUrl({trackPage: true});
+          });
         });
       });
     }
diff --git a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
index 78b7351..cfcc1a8 100644
--- a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
+++ b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.module
@@ -17,6 +17,21 @@ function openseadragon_bookmark_url_preprocess_field(&$variables) {
     foreach ($variables['items'] as $item) {
       if (isset($item['content']['#theme']) && $item['content']['#theme'] == 'openseadragon_formatter') {
         $variables['#attached']['library'][] = 'openseadragon_bookmark_url/openseadragon_bookmark_url';
+
+        // Inject bookmark URL into settings for later reference in js.
+        $config = \Drupal::config('openseadragon_bookmark_url.settings');
+        $bookmark_url_bundle = $config->get('bookmark_url_bundle');
+        $bookmark_url_field = $config->get('bookmark_url_field');
+        if (isset($item['content']['#entity'])) {
+          $entity = $item['content']['#entity'];
+          if ($entity->bundle() == $bookmark_url_bundle) {
+            $openseadragon_viewer_id = 'openseadragon-viewer-' . $entity->id();
+            if ($entity->hasField($bookmark_url_field)) {
+              $fragment = $entity->get($bookmark_url_field)->value;
+              $variables['#attached']['drupalSettings']['openseadragon'][$openseadragon_viewer_id]['openseadragonBookmarkUrl'] = $fragment;
+            }
+          }
+        }
       }
     }
   }
diff --git a/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.services.yml b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.services.yml
new file mode 100644
index 0000000..6eca5c9
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/openseadragon_bookmark_url.services.yml
@@ -0,0 +1,5 @@
+services:
+  openseadragon_bookmark_url.config:
+    class: Drupal\openseadragon_bookmark_url\BookmarkUrlConfig
+    arguments:
+      - '@config.factory'
diff --git a/modules/openseadragon_bookmark_url/src/BookmarkUrlConfig.php b/modules/openseadragon_bookmark_url/src/BookmarkUrlConfig.php
new file mode 100644
index 0000000..ee36701
--- /dev/null
+++ b/modules/openseadragon_bookmark_url/src/BookmarkUrlConfig.php
@@ -0,0 +1,61 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Drupal\openseadragon_bookmark_url;
+
+use Drupal\Core\Config\ConfigFactoryInterface;
+use Drupal\Core\Config\ImmutableConfig;
+
+/**
+ * Typed accessor service for openseadragon_bookmark_url.settings.
+ *
+ * Centralizes all reads of the submodule's config so that callers never
+ * need to remember the config object name or key names, and so that the
+ * config object is only loaded once per request.
+ *
+ * Usage (from a service or controller):
+ * @code
+ *   $bm_config = \Drupal::service('openseadragon_bookmark_url.config');
+ *   $bundle = $bm_config->getBundle();
+ *   $field  = $bm_config->getField();
+ * @endcode
+ */
+final class BookmarkUrlConfig {
+
+  private const CONFIG_NAME = 'openseadragon_bookmark_url.settings';
+
+  private ImmutableConfig $config;
+
+  /**
+   * Constructs a BookmarkUrlConfig instance.
+   *
+   * @param \Drupal\Core\Config\ConfigFactoryInterface $configFactory
+   *   The Drupal config factory service.
+   */
+  public function __construct(ConfigFactoryInterface $configFactory) {
+    $this->config = $configFactory->get(self::CONFIG_NAME);
+  }
+
+  /**
+   * Returns the configured node bundle machine name, or an empty string.
+   */
+  public function getBundle(): string {
+    return $this->config->get('bookmark_url_bundle') ?? '';
+  }
+
+  /**
+   * Returns the configured field machine name, or an empty string.
+   */
+  public function getField(): string {
+    return $this->config->get('bookmark_url_field') ?? '';
+  }
+
+  /**
+   * Returns TRUE when both bundle and field have been set by an administrator.
+   */
+  public function isConfigured(): bool {
+    return $this->getBundle() !== '' && $this->getField() !== '';
+  }
+
+}

From fe3c041dc7d64978569e73951c3e61f7ffa4dc5a Mon Sep 17 00:00:00 2001
From: Jonathan Hunt <git@huntdesign.co.nz>
Date: Tue, 26 May 2026 12:16:37 +1200
Subject: [PATCH 9/9] #66 Add variable doc comment

---
 .../src/BookmarkUrlConfig.php                     | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/modules/openseadragon_bookmark_url/src/BookmarkUrlConfig.php b/modules/openseadragon_bookmark_url/src/BookmarkUrlConfig.php
index ee36701..3fbca09 100644
--- a/modules/openseadragon_bookmark_url/src/BookmarkUrlConfig.php
+++ b/modules/openseadragon_bookmark_url/src/BookmarkUrlConfig.php
@@ -10,21 +10,22 @@
 /**
  * Typed accessor service for openseadragon_bookmark_url.settings.
  *
- * Centralizes all reads of the submodule's config so that callers never
- * need to remember the config object name or key names, and so that the
- * config object is only loaded once per request.
- *
  * Usage (from a service or controller):
  * @code
- *   $bm_config = \Drupal::service('openseadragon_bookmark_url.config');
- *   $bundle = $bm_config->getBundle();
- *   $field  = $bm_config->getField();
+ *   $config = \Drupal::service('openseadragon_bookmark_url.config');
+ *   $bundle = $config->getBundle();
+ *   $field  = $config->getField();
  * @endcode
  */
 final class BookmarkUrlConfig {
 
   private const CONFIG_NAME = 'openseadragon_bookmark_url.settings';
 
+  /**
+   * The openseadragon bookmark url config.
+   *
+   * @var \Drupal\Core\Config\ImmutableConfig
+   */
   private ImmutableConfig $config;
 
   /**