PG in some conditions generates (and dont destroy later) some temporary schemas (like: pg_temp_x, pg_toast_temp_x). In HeidiSQL connected database content tree (left pane) lists them all because of query: SELECT "nspname" FROM "pg_catalog"."pg_namespace" ORDER BY "nspname";
Will it ruin something if query is changed to: SELECT "nspname" FROM "pg_catalog"."pg_namespace" WHERE "nspname" not ilike 'pg_temp%' and "nspname" not ilike 'pg_toast_temp%' ORDER BY "nspname"; to avoid screen waste? There may be schemas before pg_t* and after, so it need scrolling over "wasteland".
NB! Schema pg_catalog is valuable to see. It has sometimes interesting things inside :)