Viewer replace characters with square

Hello,
we have a new bug. Viewer is replacing some characters and double characters in the document with an empty square. Can you take a look at it? They are not special characters.

We are using version 25.2.

Thanks, Jan

original_doc.pdf (2.4 MB)

incorrect_characters.png (24.8 KB)

@biczdim

Could you please provide more details about the specific characters that are being replaced with squares and any additional context regarding the document format or content?

Can you look at the attachments?

@biczdim

Looking at the screenshot I can see that double character (ligature) was rendered as an box.

Unfortunately, I have failed to reproduce the issue on Windows and Linux (Docker) with this
sample-app.zip (2.2 MB).

Can you please modify the application if the code differs from the one you’re using and share more information about your environment?