the same function behaves totally differently on 12:
postgres=# \c test
psql (13.0, server 12.4)
You are now connected to database "test" as user "postgres".
test=# SELECT * FROM public.vacuum_dead_size(now());
ERROR: return type mismatch in function declared to return record
DETAIL: Final statement returns name instead of text at column 1.
CONTEXT: SQL function "vacuum_dead_size" during startup
there is been no mismatch error on 13
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