--- a/ViewerPlugin/CMakeLists.txt	Tue Nov 04 17:30:14 2025 +0100
+++ b/ViewerPlugin/CMakeLists.txt	Tue Nov 04 18:03:57 2025 +0100
@@ -37,11 +37,6 @@
 SET(USE_SYSTEM_OPENJPEG ON CACHE BOOL "Use the system version of OpenJpeg")
 SET(USE_SYSTEM_ORTHANC_SDK ON CACHE BOOL "Use the system version of the Orthanc plugin SDK")
 
-# Parameters related to OpenLayers
-SET(USE_SYSTEM_OPENLAYERS OFF CACHE BOOL "Use the system version of OpenLayers")
-SET(OPENLAYERS_CSS "" CACHE FILEPATH "Path to the system version of OpenLayers CSS")
-SET(OPENLAYERS_JS "" CACHE FILEPATH "Path to the system version of OpenLayers JavaScript")
-
 
 #####################################################################
 ## Configure mandatory third-party components
@@ -146,37 +141,13 @@
 
 
 #####################################################################
-## Prepare OpenLayers
+## Prepare JavaScript libraries
 #####################################################################
 
-if (STATIC_BUILD OR NOT USE_SYSTEM_OPENLAYERS)
-  DownloadPackage(
-    "b7de8bba890ccc3858920bd66dd79d2d"
-    "https://orthanc.uclouvain.be/downloads/third-party-downloads/WSI/openlayers-10.6.1-package.tar.gz"
-    "openlayers-10.6.1-package")
-  
-  set(OPENLAYERS_RESOURCES
-    OPENLAYERS_CSS  ${CMAKE_CURRENT_BINARY_DIR}/openlayers-10.6.1-package/ol.css
-    OPENLAYERS_JS   ${CMAKE_CURRENT_BINARY_DIR}/openlayers-10.6.1-package/dist/ol.js
-    )
-
-else()
-  if (OPENLAYERS_CSS STREQUAL "")
-    message(FATAL_ERROR "The option OPENLAYERS_CSS is not set")
-  endif()
-
-  if (OPENLAYERS_JS STREQUAL "")
-    message(FATAL_ERROR "The option OPENLAYERS_JS is not set")
-  endif()
-
-  set(OPENLAYERS_RESOURCES
-    OPENLAYERS_CSS  ${OPENLAYERS_CSS}
-    OPENLAYERS_JS   ${OPENLAYERS_JS}
-    )  
-endif()
+include(${CMAKE_SOURCE_DIR}/../Resources/CMake/JavaScriptLibraries.cmake)
 
 EmbedResources(
-  ${OPENLAYERS_RESOURCES}
+  JAVASCRIPT_LIBS      ${JAVASCRIPT_LIBS_DIR}
   ORTHANC_EXPLORER     ${CMAKE_SOURCE_DIR}/OrthancExplorer.js
   VIEWER_HTML          ${CMAKE_SOURCE_DIR}/viewer.html
   VIEWER_JS            ${CMAKE_SOURCE_DIR}/viewer.js

--- a/ViewerPlugin/Plugin.cpp	Tue Nov 04 17:30:14 2025 +0100
+++ b/ViewerPlugin/Plugin.cpp	Tue Nov 04 18:03:57 2025 +0100
@@ -362,6 +362,35 @@
 }
 
 
+void ServeJavaScriptLibraries(OrthancPluginRestOutput* output,
+                              const char* url,
+                              const OrthancPluginHttpRequest* request)
+{
+  OrthancPluginContext* context = OrthancPlugins::GetGlobalContext();
+
+  if (request->method != OrthancPluginHttpMethod_Get)
+  {
+    OrthancPluginSendMethodNotAllowed(context, output, "GET");
+  }
+  else
+  {
+    const std::string path = "/" + std::string(request->groups[0]);
+    const char* mime = Orthanc::EnumerationToString(Orthanc::SystemToolbox::AutodetectMimeType(path));
+
+    if (path == "/js/ol.js")
+    {
+      // Adding "charset" is mandatory with OpenLayers 10.4.0, check out "zoomOutLabel" in the source code
+      mime = "application/javascript; charset=utf-8";
+    }
+
+    std::string s;
+    Orthanc::EmbeddedResources::GetDirectoryResource(s, Orthanc::EmbeddedResources::JAVASCRIPT_LIBS, path.c_str());
+
+    const char* resource = s.size() ? s.c_str() : NULL;
+    OrthancPluginAnswerBuffer(context, output, resource, s.size(), mime);
+  }
+}
+
 
 void ServeFile(OrthancPluginRestOutput* output,
                const char* url,
@@ -382,18 +411,6 @@
     resource = Orthanc::EmbeddedResources::VIEWER_JS;
     mime = "application/javascript";
   }
-  else if (f == "dist/ol.js")
-  {
-    resource = Orthanc::EmbeddedResources::OPENLAYERS_JS;
-
-    // Adding "charset" is mandatory with OpenLayers 10.4.0, check out "zoomOutLabel" in the source code
-    mime = "application/javascript; charset=utf-8";
-  }
-  else if (f == "ol.css")
-  {
-    resource = Orthanc::EmbeddedResources::OPENLAYERS_CSS;
-    mime = "text/css";
-  }
   else if (f == "mirador.html")
   {
     resource = Orthanc::EmbeddedResources::MIRADOR_HTML;
@@ -520,8 +537,7 @@
 
     OrthancPluginRegisterOnChangeCallback(OrthancPlugins::GetGlobalContext(), OnChangeCallback);
 
-    OrthancPlugins::RegisterRestCallback<ServeFile>("/wsi/app/(ol.css)", true);
-    OrthancPlugins::RegisterRestCallback<ServeFile>("/wsi/app/(dist/ol.js)", true);
+    OrthancPlugins::RegisterRestCallback<ServeJavaScriptLibraries>("/wsi/libs/(.*)", true);
     OrthancPlugins::RegisterRestCallback<ServeFile>("/wsi/app/(viewer.html)", true);
     OrthancPlugins::RegisterRestCallback<ServeFile>("/wsi/app/(viewer.js)", true);
     OrthancPlugins::RegisterRestCallback<ServePyramid>("/wsi/pyramids/([0-9a-f-]+)", true);

--- a/ViewerPlugin/viewer.html	Tue Nov 04 17:30:14 2025 +0100
+++ b/ViewerPlugin/viewer.html	Tue Nov 04 18:03:57 2025 +0100
@@ -1,10 +1,12 @@
 <!DOCTYPE html>
 
-<html>
+<html lang="en">
   <head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title>Orthanc for Whole-Slide Imaging</title>
 
-    <link rel="stylesheet" href="ol.css" type="text/css">
+    <link rel="stylesheet" href="../libs/css/ol.css" type="text/css">
 
     <style>
       html,
@@ -28,7 +30,7 @@
     <!-- This is the version of jQuery that is used by Orthanc Explorer -->
     <script src="../../app/libs/jquery.min.js"></script>
 
-    <script src="dist/ol.js"></script>
+    <script src="../libs/js/ol.js"></script>
     <script src="viewer.js"></script>
   </body>
 </html>