I receive an email with a PDF document every week. Until I was using Windows everything was ok, but now that I'm happy Linux Mint user I found out that the content is unreadable.
I started my Windows VM only to find out that the PDF is unreadable under Chrome in exactly the same manner as under Firefox on Linux.
Then I noticed the "Open with" option and decided to give Adobe Reader a try. It was showing the content correctly. I had a look at the fonts used in the doc and found there "Verdana".
Then it all come into place. Microsoft fonts are licensed, so they are not included by default with Linux distros.
I made a search and found out that there is a special package called "MS Core Fonts Installer". A search in Mint's Software Manager revealed the exact name and after two clicks, and my promise that I won't sell the Microsoft precious fonts for billions of dollars when everyone can download them for free, I got the files on my system.
A fast check and ... 50/50 result. I could open the PDF with Document Viewer, but Chrome & Firefox failed to show any meaningful data. Well fair enough. At least I can now check the content with an additional click.