BadAlloc insufficient resources in X_OpenFont

[Julian Bradfield]

>From time to time I get this error in my xemacs running on Ubuntu
20.04 at work.

I use a lot of large core fonts, and I can imagine that there may be
some anciently-sized limit on the amount of memory the server uses for
core fonts. Or possibly there is some problem with one of the fonts.
However, it's hard to reproduce on demand - it may require some spammy
message loading an unusual charset or something - and X protocol
errors are not informative. Is there anything I can to do find out
what's wrong that's easier than running in XSync mode and tracing X
events (perhaps for days at a time!)?

If anybody has experience in this sort of problem, I'd be grateful for
advice - I can't find any via Google!