[Bug]: PDF.js Displays Incorrect Font Family (Defaults to Sans-Serif Instead of Embedded Fonts)

[AmanKrr]

Attach (recommended) or Link to PDF file

adient-test (1).pdf

Web browser and its version

Chrome 133.0.6943.99

Operating system and its version

Mac Air M1 - MacOs 15.3

PDF.js version

v4.10.38

Is the bug present in the latest PDF.js version?

Yes

Is a browser extension

No

Steps to reproduce the problem

1. Load a PDF file.
2. Inspect the rendered text and check the font family.
3. Notice that the font displayed is sans-serif, which is the default assigned by PDF.js.

What is the expected behavior?

The font family should match the one specified in the PDF document, such as Georgia or Times New Roman, instead of defaulting to sans-serif.

What went wrong?

After comparing the rendering in Adobe Acrobat and PDF.js, it was observed that PDF.js is extracting a different font family than expected. While Adobe Acrobat correctly renders the fonts as Georgia or Times New Roman, PDF.js defaults to sans-serif across all pages. This discrepancy indicates that PDF.js is not properly detecting or applying the embedded fonts from the PDF.

Link to a viewer

No response

Additional context

I have implemented a custom PDF viewer instead of using the default PDF.js viewer. However, I am utilizing PDF.js functionalities for text layer rendering and the annotation layer.

Regarding the screenshot, I intentionally included the search highlight to clearly showcase the font discrepancy. The canvas layer correctly renders the fonts, but when inspecting the text layer, it defaults to sans-serif instead of the expected font (e.g., Georgia or Times New Roman).

Additionally, when calling page.getTextContent(), the returned text content includes styles where the font is set to sans-serif. This suggests that PDF.js is not correctly extracting or applying the embedded fonts in the text layer.

Could you confirm whether this is the expected behavior?
If not, is there any recommended approach to ensure that the text layer correctly reflects the embedded fonts from the PDF?

Since no updates on this issue #19492 I had to re-create this new issue.