--- a/ViewerPlugin/Plugin.cpp	Tue Sep 01 11:38:06 2026 +0200
+++ b/ViewerPlugin/Plugin.cpp	Tue Sep 01 11:41:23 2026 +0200
@@ -408,16 +408,6 @@
     resource = Orthanc::EmbeddedResources::OPEN_SEADRAGON_HTML;
     mime = "text/html";
   }
-  else if (f == "annotations.js")
-  {
-#if ORTHANC_STANDALONE == 0
-    throw Orthanc::OrthancException(Orthanc::ErrorCode_InternalError);
-#else
-    resource = Orthanc::EmbeddedResources::ANNOTATIONS_JS;
-#endif
-
-    mime = "application/javascript";
-  }
   else
   {
     throw Orthanc::OrthancException(Orthanc::ErrorCode_UnknownResource);
@@ -439,8 +429,7 @@
 
   std::string filename(request->groups[0]);
 
-  if (filename != "annotations.js" &&
-      filename != "viewer.html" &&
+  if (filename != "viewer.html" &&
       filename != "viewer.js")
   {
     throw Orthanc::OrthancException(Orthanc::ErrorCode_UnknownResource);
@@ -588,17 +577,6 @@
       OrthancPlugins::RegisterRestCallback<ServeFramePyramid>("/wsi/frames-pyramids/([0-9a-f-]+)/([0-9-]+)", true);
       OrthancPlugins::RegisterRestCallback<ServeFrameTile>("/wsi/frames-tiles/([0-9a-f-]+)/([0-9-]+)/([0-9-]+)/([0-9-]+)/([0-9-]+)", true);
 
-      if (true)  // TODO - Protect by some configuration option
-      {
-        RegisterAnnotationsRestApi();
-
-#if ORTHANC_STANDALONE == 1
-        OrthancPlugins::RegisterRestCallback<ServeEmbeddedFile>("/wsi/app/(annotations.js)", true);
-#else
-        OrthancPlugins::RegisterRestCallback<ServeSourceFile>("/wsi/app/(annotations.js)", true);
-#endif
-      }
-
       const bool enableIIIF = OrthancWSI::ViewerConfiguration::GetInstance().IsIIIFEnabled();
       bool serveMirador = false;
       bool serveOpenSeadragon = false;
@@ -655,6 +633,9 @@
 
         OrthancPlugins::ExtendOrthancExplorer(ORTHANC_PLUGIN_NAME, explorer);
       }
+
+      // New in WSI 4.0
+      RegisterAnnotationsRestApi();
     }
     catch (Orthanc::OrthancException& e)
     {

--- a/ViewerPlugin/WebApplication/annotations.js	Tue Sep 01 11:38:06 2026 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,232 +0,0 @@
-/**
- * Orthanc - A Lightweight, RESTful DICOM Store
- * Copyright (C) 2012-2016 Sebastien Jodogne, Medical Physics
- * Department, University Hospital of Liege, Belgium
- * Copyright (C) 2017-2023 Osimis S.A., Belgium
- * Copyright (C) 2024-2026 Orthanc Team SRL, Belgium
- * Copyright (C) 2021-2026 Sebastien Jodogne, ICTEAM UCLouvain, Belgium
- *
- * This program is free software: you can redistribute it and/or
- * modify it under the terms of the GNU Affero General Public License
- * as published by the Free Software Foundation, either version 3 of
- * the License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Affero General Public License for more details.
- * 
- * You should have received a copy of the GNU Affero General Public License
- * along with this program. If not, see <http://www.gnu.org/licenses/>.
- **/
-
-
-function CreateSerializationObject()
-{
-  var serialized = {};
-
-  const params = new URLSearchParams(document.location.search);
-  if (params.has('project')) {
-    serialized['project'] = params.get('project');
-  }
-
-  if (params.has('series')) {
-    serialized['level'] = 'series';
-    serialized['resource'] = params.get('series');
-  } else if (params.has('instance')) {
-    serialized['level'] = 'instance';
-    serialized['resource'] = params.get('instance');
-  } else {
-    console.error('No series/instance available');
-  }
-
-  return serialized;
-}
-
-
-function SerializeFeature(feature)
-{
-  var type = feature.getGeometry().getType();
-
-  if (type === 'LineString') {
-    return {
-      'type' : 'polyline',
-      'coordinates' : feature.getGeometry().getCoordinates()
-    };
-  } else if (type === 'Point') {
-    return {
-      'type' : 'point',
-      'coordinates' : feature.getGeometry().getCoordinates()
-    };
-  } else if (type === 'Circle') {
-    return {
-      'type' : 'circle',
-      'center' : feature.getGeometry().getCenter(),
-      'radius' : feature.getGeometry().getRadius()
-    };
-  } else if (type === 'Polygon') {
-    return {
-      'type' : 'polygon',
-      'coordinates' : feature.getGeometry().getCoordinates()
-    };
-  } else {
-    console.error('Not implemented: ' + type);
-    return null;
-  }
-}
-
-
-function UnserializeFeature(json)
-{
-  if (json.type === 'polyline') {
-    return new ol.geom.LineString(json['coordinates']);
-  } else if (json.type === 'point') {
-    return new ol.geom.Point(json['coordinates']);
-  } else if (json.type === 'circle') {
-    return new ol.geom.Circle(json['center'], json['radius']);
-  } else if (json.type === 'polygon') {
-    return new ol.geom.Polygon(json['coordinates']);
-  } else {
-    console.error('Not implemented: ' + json.type);
-    return null;
-  }
-}
-
-
-function SerializeLayers(source)
-{
-  var features = [];
-
-  source.getFeatures().forEach((feature, index) => {
-    var item = SerializeFeature(feature);
-
-    if (item !== null) {
-      item['layer-id'] = feature.get('layer-id');
-      features.push(item);
-    }
-  });
-
-  var serialized = CreateSerializationObject();
-
-  serialized['annotations'] = {
-    'layers' : layers,
-    'features' : features
-  };
-
-  return serialized;
-}
-
-
-var sourceToSerialize = null;
-var isPendingChange = false;
-var isSaving = false;
-
-function SaveAnnotations()
-{
-  function BeforeUnloadHandler(event)
-  {
-    event.preventDefault();
-
-    // Included for legacy support, e.g. Chrome/Edge < 119
-    event.returnValue = true;
-  };
-
-  function Execute()
-  {
-    console.assert(sourceToSerialize !== null);
-
-    var serialized = SerializeLayers(sourceToSerialize);
-
-    isPendingChange = false;
-    isSaving = true;
-    $('#toolbar-spinner').show();
-    window.addEventListener('beforeunload', BeforeUnloadHandler);
-
-    $.ajax({
-      type : 'POST',
-      url : '../api/save-annotations',
-      data : JSON.stringify(serialized),
-      contentType: 'application/json',
-      success: function() {
-      },
-      error: function() {
-        alert('Cannot save the annotations');
-      },
-      complete : function() {
-        console.assert(isSaving === true);
-
-        if (isPendingChange) {
-          Execute();
-        } else {
-          isSaving = false;
-          $('#toolbar-spinner').hide();
-          window.removeEventListener('beforeunload', BeforeUnloadHandler);
-        }
-      }
-    });
-  }
-
-  if (sourceToSerialize !== null) {
-    isPendingChange = true;
-
-    if (!isSaving) {
-      Execute();
-    }
-  }
-}
-
-
-function LoadAnnotations(source)
-{
-  console.assert(sourceToSerialize === null);
-
-  $('#toolbar-spinner').show();
-
-  $.ajax({
-    type : 'POST',
-    url : '../api/load-annotations',
-    data : JSON.stringify(CreateSerializationObject()),
-    contentType: 'application/json',
-    success: function(data) {
-      if ('layers' in data &&
-          'features' in data &&
-          data['layers'].length != 0) {
-        layers = data.layers;
-        activeLayerId = data.layers[0].id;
-
-        source.clear();
-        for (let i = 0; i < data.features.length; i++) {
-          var layerId = data.features[i]['layer-id'];
-
-          if (layerId !== undefined) {
-            var geometry = UnserializeFeature(data.features[i]);
-
-            if (geometry !== null) {
-              var feature = new ol.Feature(geometry);
-              feature.set('layer-id', layerId);
-              source.addFeature(feature);
-            }
-          }
-        }
-      }
-
-      RenderLayersTable();
-
-      sourceToSerialize = source;
-      // Now that the features are loaded, we can install the save callback
-      source.on('addfeature', function (e) {
-        SaveAnnotations();
-      });
-      source.on('removefeature', function (e) {
-        SaveAnnotations();
-      });
-    },
-    error: function() {
-      console.error('Cannot load the saved annotations');
-      $('#alert-no-saving').removeClass('d-none');
-    },
-    complete: function() {
-      $('#toolbar-spinner').hide();
-    }
-  });
-}