Re: "PANIC: could not open critical system index 2662" - twice

sudo -u postgres psql -w -p 5434 -d "options='-P'"

(make that -d "dbname=whatever options='-P'"  if you need to specify
some database name; or use PGOPTIONS="-P" in the environment.)

Thanks, good to know! Unfortunately that also fails:

# sudo -u postgres psql -w -p 5434 -d "dbname=test_behavior_638186279733138190 options='-P'"
psql: error: connection to server on socket "/var/run/postgresql/.s.PGSQL.5434" failed: FATAL:  could not open relation with OID 2964

(PG server log contains the same error message and no further details.)

select 2964::regclass returns "pg_db_role_setting" FWIW.