Alter default privileges for role
janerole has been granted ALL privileges and johnrole has only been granted the SELECT privilege.


You got at least one aspect of the command backwards in all your attempts:
Alter default privileges for the role that creates objects - which in turn grants privileges to another role. I.e.:

ALTER DEFAULT PRIVILEGES FOR ROLE janerole IN SCHEMA public
GRANT SELECT ON TABLES TO johnrole;

Do this while logged in as janerole (or a member of the role).

Note that default privileges only apply to the target role, not to members of this role.

And don't forget to GRANT USAGE ON SEQUENCES as well if you have any serial columns. Possibly SELECT and UPDATE, too.

There may be more problems, the question is not completely clear.

Related:


How to manage DEFAULT PRIVILEGES for USERs on a DATABASE vs SCHEMA?
Can&#39;t alter default privileges


Note: There is an open bug in pgAdmin, the display can be incorrect (still kicking in the current pgAdmin 1.22).