Facebook stubbornly refuses to load pictures

Less than a week ago, FB suddenly stopped loading all pictures (some load, others do not, no discernible pattern). I have done a ton of research/troubleshooting. If the solution can be found in a page linked to a search "facebook pictures not loading" I've tried it. Sometimes multiple times. Tho TBF it's a whole bunch of pages repeating the same dozen or so "fixes" half of which apply only to mobile devices.

I am on a PC, windows 10, Firefox. Both are the latest updates. I checked--the latest FF did not coincide with initiation of the problem--neither did the windows updates. I checked to see if there were any windows updates that might help. there weren't. Internet is via Comcast cable, very fast connection... that is not the issue.
I don't actually believe Firefox IS the problem, as I DL'd and installed Chrome and had the same issue. FB on my phone app also has this problem, but doesn't seem as bad. FF doesn't have any ad blocker addons. I use FB Container addon, but I already confirmed that is not the problem. I tried allowing FB to run without enhanced tracking on, no happiness. The only other addons are Browse Safe powered by Yahoo, DuckDuckGo Privacy Essentials, Mailvelope, and Native MPEG-Dash + HLS Playback... none of these are new... they've been there for ages. I created a completely new, unlinked FB account. It also had the same problem. Looked for updates for the video card (GTX 1070 Ti, so kinda old, but runs just fine). They stopped updating those drivers... end of life. The current one is about 2 yrs old, but again, it works just fine playing graphics intensive games.

The computer is used a lot, but not for a lot of different things. Email, FB, looking up various things on DuckDuckGo, Discord, and Elder Scrolls online game. I've experienced no problems with any of these things. I'm pretty much at a loss here, so any additional suggestions would be most welcome. But like I said, if the possible "solution" pops up on a search for this issue, I've almost certainly already done it.