The following documentation comment has been logged on the website:
Page: https://www.postgresql.org/docs/13/sql-createfunction.html
Description:
| IMMUTABLE | STABLE | VOLATILE | [ NOT ] LEAKPROOF
[ NOT ] LEAKPROOF is accepting separately ,
So why you written [ NOT ] LEAKPROOF with | IMMUTABLE | STABLE | VOLATILE |
Please separate the [ NOT ] LEAKPROOF from the OR list
Note: Your documentation must be correct