Did you try Firefox in Troubleshoot Mode? https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode#search104 What OS? What version of Firefox?

I just tried Troubleshoot mode and still doesn't show the missing information.

OS 10.15.7 Firefox 130.0

That's very strange. I have not seen a pdf do that in Firefox yet. I think Blue Cross Blue Shield added a new font to the text that is missing & Firefox doesn't recognize it. If we can get another pdf showing the problem without all the sensitive information, the Firefox developers can investigate & fix it.

But don't worry, don't share your pdf with anyone. Eventually this problem will show up again on a regular pdf & then we can submit that for investigation.

For now, I would either use the free PDF reader called Foxit PDF Reader or the Chrome browser until we can get this fixed. That PDF reader is not made by us. It just has a similar name but its very good at reading PDFs.