i have made progress on bisecting the issue i posted. the host is behind cloudflare :/ . that seems like a big possible related factor. the error does not happen when i run curl simultaneously to the failing request (prior, terminates after start, or after, terminates before end). so big suspects include triggering on headers, personal hallucination, system compromise. as it try to diagnose it my muscles contract and begin kind of vibrating, in ways that pull me away from what i'm doing. my body constantly tries to make errors that harm my work: i already ctrl-c'd one long-running process when i was trying to just rerun a test without ctrl-c'ing anything. i'd really like to video or eeg these weird personal misbehaviors. log storage first, though, or i'll just delete the log!