Can you show and or provide use something to see? Can we have access to an example pdf?

Is this about links to local files of files on internet ?

Do you have the MSIX Firefox version from the Microsoft Store?

• https://support.mozilla.org/en-US/kb/download-firefox-windows-microsoft-store

There was a bug four years ago that was fixed in Firefox 78 where Firefox's built-in PDF viewer couldn't open a PDF attached to the PDF. Here is my old demo file for that bug -- the attachment opens for me today:

https://www.jeffersonscher.com/temp/Links-attachments-PDFs.pdf

What happens when you try to open the PDF?

There was a report in August 2020 that one of the EasyList filters would immediately close the tab with the attached PDF as part of it's popup protection. If you are seeing a tab open then immediately close, perhaps the problem is along those lines.

See also this thread created by the OP (berygan) because of issues with trying to reply .

• /questions/1440080 Cannot open attachement of PDF files

Hi, is it a Firefox issue? I can't see Firefox on the attached screenshot.

The attachments are highlighted in blue in the opened PDF file but cannot be opened.

I don't think there's such a thing like attachments in PDF.

Hi, is it a Firefox issue? I can't see Firefox on the attached screenshot.

The attachments are highlighted in blue in the opened PDF file but cannot be opened.

I don't think there's such a thing like attachments in PDF.

I was thinking the same thing and found this.  ;-)) https://www.google.com/search?client=firefox-b-1-e&q=Attachement+in+PDF+Files

Aha, thanks for the screenshot from the other thread (https://assets-prod.sumo.prod.webservices.mozgcp.net/media/uploads/images/2024-02-18-13-24-46-ed4aef.png). I think this is the key area:

Firefox's "Save to PDF" feature can preserve web links, but I don't know whether email attachments can be accessed using web links.

I assume the links do not open in a browser, so they are not web links?

Since you are viewing the PDF in Acrobat, could you check the attachments list for the PDF? The icon for it is a paper clip on the right side:

If the two images are listed there, you should be able to access them using that list, even if the links aren't working. If the two images are NOT listed there, then they weren't captured when the PDF was created.

See also:

• /questions/1440104 Cannot open PDF attachements in Firefox