Minecraft popped up a problem report showing CodeChicken Lib, Draconic Evolution, and Brandon's Core as potential causes of the problem. This showed up while linking Draconic Ev. crystals. I should mention I had a significant PC crash about 2 weeks ago that messed with this world a bit. I haven't found a lot of effects, but it did mess with both Refined Storage (predictably) and Astral Sorcery, so that crash may be key here.

In any case, I'm attaching the text crash report. I'm not sure there's anything I need, unless there's something I should do to avoid further problems. This is a world I use for a streaming series, so I'm really hoping to keep it running.

NOTE: As I went to attach the file, I discovered there are 4 of them. That syncs up with the 4 links I was creating at about that time.
crash-2020-04-12_15.02.57-client.txt
crash-2020-04-12_15.02.52-client.txt
crash-2020-04-12_15.02.55-client.txt
crash-2020-04-12_15.02.56-client.txt