Cannot download files from Canvas/Instructure

Around May 7th or 8th, Canvas, the web-based learning management system was hacked. I don't know the nature of the data breach but Canvas was offline for a while. My college's IT department gave the all-clear to use Canvas shortly after it came back online, but I can no longer receive any of the file data from what I try to download off Canvas, it just gives me an empty file with 0KB of data. I cannot find anywhere in the settings to whitelist Canvas so that I can receive file data.

Is there any user-side solution to this, or does Mozilla need to be the ones to fix this? This is impeding my ability to do class work on Firefox, and I have to switch to a different browser to open the PDFs that my professors post on Canvas. I mainly use Firefox for iOS, but I have classmates who said they are experiencing the same problem with the Windows version of Firefox.