What functionality is missing? What is unsatisfying with the current situation?

Currently you can add files in JPG, JPEG, PNG, GIF, and Webp formats to the Images & Files section. It would be amazing if you could also add PDFs and be able to link them to articles, NPCs, and Statblocks. Maybe you could even create a Statblock that IS a pdf!  

How does this feature request address the current situation?

The reason that I need it is that would make it easier to see all the necessary information about NPCs. I could create character sheets for them (or use a program that does this automatically) and add that to the NPC in question. That way, if my players ever happen to get into a fight with this NPC near, I can hop them into the fight without having to take pauses to check their abilities.  

What are other uses for this feature request?

This could be used in many different ways! If a player sends their PC's background with a pdf, you can add that to them with a few clicks! And illustrated spell cards a

That is not going to be possible. PDFs are notoriously carriers of trojans and other malicious content also there is no way to preview it on WA