In the same way that you can add a comment on a table or column, it would be useful to be able to add a comment on a trigger. A trigger is an object and adding comments on triggers would be helpful.
COMMENT ON TABLE schema.table IS
'This is my comment.';
COMMENT ON COLUMN schema.table.column IS
‘This is my comment.’;
COMMENT ON TRIGGER schema.trigger IS
'This is my comment.';