Trying to set a constraint - a new primary key in the table, but get an error: the column "amgettuple" does not exist (pgadmin3)

Question

I create a new table using pgadmin3, and when I click on the restrictions to add the primary key, I get this error:

I searched on google but I did not find this "amgettuple" problem. Does anyone know what this means? I am new to postgres and use pgadmin, just installed it an hour ago.

Postgres Version: 9.6

pgadmin version: 1.22.2

linux mint 18

Answer 1

Install pgAdmin 4. pgAdmin III was supported before version 9.5, I think.