# Parts of PDF text are not displayed - like whiteout has been wiped across

**URL:** <https://pdfjs.community/t/parts-of-pdf-text-are-not-displayed-like-whiteout-has-been-wiped-across/1895>\
**Category:** Technical Support\
**Tags:** pdfjs-express\
**Created:** [July 22, 2022, 10:45am UTC](https://pdfjs.community/t/parts-of-pdf-text-are-not-displayed-like-whiteout-has-been-wiped-across/1895 "2022-07-22T10:45:04Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![nickmyersdt](https://yyz1.discourse-cdn.com/flex031/user_avatar/pdfjs.community/nickmyersdt/32/628_2.png) [@nickmyersdt](https://pdfjs.community/u/nickmyersdt)\
**Post date:** [July 22, 2022, 10:45am UTC](https://pdfjs.community/t/parts-of-pdf-text-are-not-displayed-like-whiteout-has-been-wiped-across/1895/1 "2022-07-22T10:45:05Z")

</div>

**Which product are you using?**  
@pdftron/pdfjs-express-viewer

**PDF.js Express Version**  
8.1.1

**Detailed description of issue**  
Really odd issue, which I expect is not caused by pdfjs-express-viewer however I’m hoping that people on this forum may have encountered it before.

In short, a small number of Windows 10 / Chrome users have reported that when they view SOME of our PDFs, using pdfjs-express-viewer have this rather strange display issue:

 ![Capture](https://canada1.discourse-cdn.com/flex031/uploads/pdfjscommunity/original/1X/3480d209df72a9700a80239063a19046bd835a13.png)

Updating OS, Browser and Graphics Drivers have had no effect, neither has enabling/disabling Hardware Acceleration.

Users tell us that the “whiteout” disappears if they “zoom in a lot” (to the point where they can’t read it without a lot of scrolling).

Microsoft Windows 10 Pro 10.0.19044  
Google Chrome 103.0.5060.134  
NVIDIA(R) GeForce(R) MX330 with 2GB GDDR5 graphics memory

**Expected behaviour**

Text displays normally.

**Does your issue happen with every document, or just one?**  
SOME PDFs, not all.

**Link to document**  
Removed.

**Code snippet**  
N/A (I think)

Whilst no errors appear in Chrome, the issue persists in Edge, and this message appears:

```javascript
 TT: undefined function: 32 pdf.worker.js

```

Any ideas would be really appreciated.

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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:** [July 22, 2022, 10:45am UTC](https://pdfjs.community/t/parts-of-pdf-text-are-not-displayed-like-whiteout-has-been-wiped-across/1895/3 "2022-07-22T10:45:10Z")

</div>

**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:

Guides:
- [PDF.js Express Viewer Overview - What is PDF.js Express Viewer?](https://pdfjs.express/documentation/get-started-viewer#what-is-pdf.js-express-viewer?)
- [Adding your license key - PDF.js Express Viewer License Keys](https://pdfjs.express/documentation/get-started/add-license-key#pdf.js-express-viewer-license-keys-<span-class='viewer'></span>)
- [Browser support for PDF.js Express](https://pdfjs.express/documentation/learn-more/browser-support)

APIs:
- [Core.DocumentViewer - refreshAll()](https://pdfjs.express/api/Core.DocumentViewer.html#refreshAll__anchor)
- [ExpressUtils(optionsopt) - # async extract() → {Promise.}](https://pdfjs.express/api/utils/ExpressUtils.html#extract__anchor)
- [PDF.js Express Utilities](https://pdfjs.express/api/utils/index.html#__anchor)

Forums:
- [PDF.js Express Viewer not working via reverse proxies](https://pdfjs.community/t/pdf-js-express-viewer-not-working-via-reverse-proxies/1255/1)
- [PDF.js Express Viewer Watermarks](https://pdfjs.community/t/pdf-js-express-viewer-watermarks/1614/1)
- [Pdf.js Express Viewer rendering issue on live site](https://pdfjs.community/t/pdf-js-express-viewer-rendering-issue-on-live-site/1584/1)

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<div class="post-metadata">

**Author:** ![tgordon](https://avatars.discourse-cdn.com/v4/letter/t/aca169/32.png) [@tgordon](https://pdfjs.community/u/tgordon)\
**Post date:** [July 22, 2022, 5:21pm UTC](https://pdfjs.community/t/parts-of-pdf-text-are-not-displayed-like-whiteout-has-been-wiped-across/1895/4 "2022-07-22T17:21:57Z")

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Hello nickmyersdt,

This is similar issue that we have seen, see this community post on how to work around it: [Choppy text rendered with Windows and Chrome - FAQ - PDFTron Community](https://community.pdftron.com/t/choppy-text-rendered-with-windows-and-chrome/6034)  
it also has more information regarding the issue.

Best regards,  
Tyler Gordon  
Web Development Support Engineer  
PDFTron

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<div class="post-metadata">

**Author:** ![nickmyersdt](https://yyz1.discourse-cdn.com/flex031/user_avatar/pdfjs.community/nickmyersdt/32/628_2.png) [@nickmyersdt](https://pdfjs.community/u/nickmyersdt)\
**Post date:** [July 23, 2022, 6:40am UTC](https://pdfjs.community/t/parts-of-pdf-text-are-not-displayed-like-whiteout-has-been-wiped-across/1895/5 "2022-07-23T06:40:52Z")

</div>

Thank you Tyler! That looks identical, we’ll make a note of that and give the workaround a go ourselves.

You have saved me from endless trawling of search results trying to describe the visual effect accurately!