IIRC, it was lemmy.ca full copy of live data that was used (copy made on development system, not live server - if I’m following). Shared Saturday July 22 on GitHub was this procedure:

…

Notable is the AUTO_EXPLAIN SQL activation statements:

LOAD 'auto_explain';
SET auto_explain.log_min_duration = 0;
SET auto_explain.log_analyze = true;
SET auto_explain.log_nested_statements = true;

This technique would be of great use for developers doing changes and study of PostgreSQL activity. Thank you!