diff --git a/web/pdf_link_service.js b/web/pdf_link_service.js
index a89cdd72a..2f1485598 100644
--- a/web/pdf_link_service.js
+++ b/web/pdf_link_service.js
@@ -228,13 +228,11 @@ var PDFLinkService = (function () {
           this.page = pageNumber; // simple page
         }
         if ('pagemode' in params) {
-          if (params.pagemode === 'thumbs' || params.pagemode === 'bookmarks' ||
-              params.pagemode === 'attachments') {
-            this.switchSidebarView((params.pagemode === 'bookmarks' ?
-                                   'outline' : params.pagemode), true);
-          } else if (params.pagemode === 'none' && this.sidebarOpen) {
-            document.getElementById('sidebarToggle').click();
-          }
+          var event = document.createEvent('CustomEvent');
+          event.initCustomEvent('pagemode', true, true, {
+            mode: params.pagemode,
+          });
+          this.pdfViewer.container.dispatchEvent(event);
         }
       } else if (/^\d+$/.test(hash)) { // page number
         this.page = hash;
diff --git a/web/viewer.js b/web/viewer.js
index cbeda49ef..f5d82b5ca 100644
--- a/web/viewer.js
+++ b/web/viewer.js
@@ -1566,6 +1566,30 @@ document.addEventListener('textlayerrendered', function (e) {
 //#endif
 }, true);
 
+document.addEventListener('pagemode', function (evt) {
+  if (!PDFViewerApplication.initialized) {
+    return;
+  }
+  // Handle the 'pagemode' hash parameter, see also `PDFLinkService_setHash`.
+  var mode = evt.detail.mode;
+  switch (mode) {
+    case 'bookmarks':
+      // Note: Our code calls this property 'outline', even though the
+      //       Open Parameter specification calls it 'bookmarks'.
+      mode = 'outline';
+      /* falls through */
+    case 'thumbs':
+    case 'attachments':
+      PDFViewerApplication.switchSidebarView(mode, true);
+      break;
+    case 'none':
+      if (PDFViewerApplication.sidebarOpen) {
+        document.getElementById('sidebarToggle').click();
+      }
+      break;
+  }
+}, true);
+
 document.addEventListener('namedaction', function (e) {
   // Processing couple of named actions that might be useful.
   // See also PDFLinkService.executeNamedAction