BUG #16670: pgstattuple ERROR: relation "sql_implementation_info" does not exist

The following bug has been logged on the website:

Bug reference: 16670
Logged by: Marc Rechté
Email address: mrechte(at)gmail(dot)com
PostgreSQL version: 13.0
Operating system: CentOS8
Description:

Hello,

I get an error with pgstattuple extension.

On PG13.0:
# select tablename,
(pgstattuple_approx(tablename::regclass)).approx_free_space from pg_tables
where schemaname = 'public' and
(pgstattuple_approx(tablename::regclass)).approx_free_percent > 10;
ERROR: relation "sql_implementation_info" does not exist

On PG12.3:
# select tablename,
(pgstattuple_approx(tablename::regclass)).approx_free_space from pg_tables
where schemaname = 'public' and
(pgstattuple_approx(tablename::regclass)).approx_free_percent > 10;
ERROR: relation "sql_packages" does not exist

Note that the where clause on approx_free_percent is the error cause.

Thanks