# PDF Express Viewer is crashing on bookmark-more-button-0 click

**URL:** <https://pdfjs.community/t/pdf-express-viewer-is-crashing-on-bookmark-more-button-0-click/3400>\
**Category:** Bug Reports\
**Created:** [August 12, 2024, 10:31pm UTC](https://pdfjs.community/t/pdf-express-viewer-is-crashing-on-bookmark-more-button-0-click/3400 "2024-08-12T22:31:52Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![pdfjsexpress](https://avatars.discourse-cdn.com/v4/letter/p/43a26b/32.png) [@pdfjsexpress](https://pdfjs.community/u/pdfjsexpress)\
**Post date:** [August 12, 2024, 10:31pm UTC](https://pdfjs.community/t/pdf-express-viewer-is-crashing-on-bookmark-more-button-0-click/3400/1 "2024-08-12T22:31:52Z")

</div>

Hello community!

![Bildschirmfoto 2024-08-13 um 00.21.40](https://canada1.discourse-cdn.com/flex031/uploads/pdfjscommunity/original/2X/4/41608bbedc2f528300081456819c4b5542aadbd9.png)

I added the bookmarks to the left panel and added a bookmark. When I click on the button with the three dots (data-element=“bookmark-more-button-0”) the viewer crashes with the error  
00:30:08.141 TypeError: r is null  
m Marko  
React 21  
 index.js:201  
promise callback\* index.js:184  
Webpack 3  
react-dom.production.min.js:216:199  
React 24  
 index.js:201  
(Async: promise callback)  
 index.js:184  
Webpack 3  
( react-dom.production.min.js:216:199)

00:30:08.142 Uncaught TypeError: r is null  
m Marko  
React 21  
 index.js:201  
promise callback\* index.js:184  
Webpack 3  
BookmarkOutlineContextMenuPopup.js:28:4

I tested it in Firefox v129.0 (64-Bit), Chrome v127.0.6533.100 and Safari v17.5.

My PDF Express Viewer versions:  
UI version 8.7.0  
Core version 8.7.5  
webviewer.min.js 8.7.5  
Build Ny80LzIwMjR8MzMxOTBmNGM5YQ==  
WebViewer Server false  
Full API false

My simple view set up is:

```javascript
<div id="viewer" class="h-full"></div>
    <script>
        window.addEventListener('DOMContentLoaded', () => {
            PDFJSExpress({
                path: '/pdfjsexpress',
                licenseKey: 'xxxxxxxxxxxxxx',
                initialDoc: "xxxxxxxx",
            }, document.getElementById('viewer'))
                .then(function (instance) {

                    instance.UI.enableElements(['bookmarksPanelButton','bookmarksPanel'])
                })
                .catch(err => {
                    console.error(err);
                });
        });
    </script>

```

I’m not sure if this is related to the issue, but I get also the following deprecation warning:  
‘setCustomModal’ deprecated since version 8.5. Please use UI.addCustomModal instead addCustomModal.js:82:10

Thanks for your help

---

<div class="post-metadata">

**Author:** ![darian.chen](https://avatars.discourse-cdn.com/v4/letter/d/3d9bf3/32.png) [@darian.chen](https://pdfjs.community/u/darian.chen)\
**Post date:** [August 13, 2024, 3:30pm UTC](https://pdfjs.community/t/pdf-express-viewer-is-crashing-on-bookmark-more-button-0-click/3400/3 "2024-08-13T15:30:21Z")

</div>

Hi there,

I believe this error occurs because this feature is not available on Express.

 ![image](https://canada1.discourse-cdn.com/flex031/uploads/pdfjscommunity/original/2X/b/b4fa1a41e295c152173fb546332ac30d3859797c.png)  
You can read more about the available features here: [PDF.js License Pricing for Commercial Viewer | PDF.js Express](https://pdfjs.express/pricing#features)

Best Regards,  
Darian