It seems tesseract's dev put so some code in their frontend to DDoS dbzero (there's a post about it in one of the "fediverse" communities).
Your issues may be related to that. What you're seeing may be "Anubis" or something similar (not really familiar with what the not/scraping defenses look like).
Might be worth pinging an admin to get their thoughts. Hope you're able to solve the issue.
Edit: post of potential interest: