# PDFjs Express not working in Firefox

**URL:** <https://pdfjs.community/t/pdfjs-express-not-working-in-firefox/661>\
**Category:** Technical Support\
**Created:** [March 24, 2021, 6:07am UTC](https://pdfjs.community/t/pdfjs-express-not-working-in-firefox/661 "2021-03-24T06:07:38Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![Steven](https://avatars.discourse-cdn.com/v4/letter/s/94ad74/32.png) [@Steven](https://pdfjs.community/u/Steven)\
**Post date:** [March 24, 2021, 6:07am UTC](https://pdfjs.community/t/pdfjs-express-not-working-in-firefox/661/1 "2021-03-24T06:07:38Z")

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Hi,

PDFJSExpress can’t worked on Firefox, It returns the error “NS\_ERROR\_FAILURE”. Is this the reason behind this issues?  
PDFJSExpress working fine in Google Chrome. Please provide suggestion so we can solve on our end.

 ![Screenshot_12](https://canada1.discourse-cdn.com/flex031/uploads/pdfjscommunity/original/1X/f8bb5339b59ca6633c3a46ea576e297ef818b910.png)  
 ![Screenshot_15](https://canada1.discourse-cdn.com/flex031/uploads/pdfjscommunity/original/1X/d8f71836ad52ed59c44dc6f932ca6334abb6d240.png) ![Screenshot_16](https://canada1.discourse-cdn.com/flex031/uploads/pdfjscommunity/original/1X/13d77ce1a864694762521e8c9a14035e3a2751d7.png)

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<div class="post-metadata">

**Author:** ![system](https://canada1.discourse-cdn.com/flex031/uploads/pdfjscommunity/original/1X/ffbcd25c7d423db8d5acd5db201c272f4db306dd.png) [@system](https://pdfjs.community/u/system)\
**Post date:** [March 24, 2021, 6:07am UTC](https://pdfjs.community/t/pdfjs-express-not-working-in-firefox/661/2 "2021-03-24T06:07:39Z")

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**Hello, I’m Ron, an automated tech support bot 🤖**

While you wait for one of our customer support representatives to get back to you, please check out some of these documentation pages:

- [CoreControls.DocumentViewer - new DocumentViewer()](https://pdfjs.express/api/CoreControls.DocumentViewer.html#DocumentViewer__anchor)
- [CoreControls.Document - LoadAsyncCallback( [error])](https://pdfjs.express/api/CoreControls.Document.html#.LoadAsyncCallback__anchor)
- [WebViewerInstance - exportBookmarks()](https://pdfjs.express/api/WebViewerInstance.html#exportBookmarks__anchor)
- [Vue PDF.js Viewer - Browser Support](https://pdfjs.express/documentation/vue#browser-support)
- [Svelte PDF.js Viewer - Browser Support](https://pdfjs.express/documentation/svelte#browser-support)

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<div class="post-metadata">

**Author:** ![Logan](https://yyz1.discourse-cdn.com/flex031/user_avatar/pdfjs.community/logan/32/13_2.png) [@Logan](https://pdfjs.community/u/Logan)\
**Post date:** [March 25, 2021, 3:24pm UTC](https://pdfjs.community/t/pdfjs-express-not-working-in-firefox/661/3 "2021-03-25T15:24:10Z")

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Hey there,

It looks like you are using Express inside a modal - are you setting `display: none` on that modal by chance? Firefox has a bug where setting `display:none` on an iframe or an iframes parent breaks the contents of that iframe.

To work around this bug you can instead set the element to `visibility: hidden` or `height: 0; width: 0;` .

Thanks!  
Logan

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<div class="post-metadata">

**Author:** ![Steven](https://avatars.discourse-cdn.com/v4/letter/s/94ad74/32.png) [@Steven](https://pdfjs.community/u/Steven)\
**Post date:** [March 30, 2021, 3:41am UTC](https://pdfjs.community/t/pdfjs-express-not-working-in-firefox/661/4 "2021-03-30T03:41:00Z")

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Thank you for your reply. Loaded PDFJS in ifram and it has worked of us.

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<div class="post-metadata">

**Author:** ![Logan](https://yyz1.discourse-cdn.com/flex031/user_avatar/pdfjs.community/logan/32/13_2.png) [@Logan](https://pdfjs.community/u/Logan)\
**Post date:** [March 30, 2021, 2:19pm UTC](https://pdfjs.community/t/pdfjs-express-not-working-in-firefox/661/5 "2021-03-30T14:19:47Z")

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