BUG #17099: Problem with EXECUTE and JSON

The following bug has been logged on the website:

Bug reference: 17099
Logged by: Eugene Ilushin
Email address: ineron(at)icloud(dot)com
PostgreSQL version: 11.7
Operating system: centos-release-7-6.1810.2.el7.centos.x86_64
Description:

DO $$
DECLARE
_res jsonb;
BEGIN
--EXECUTE
$sql$select(json_build_object('name','name','query','query','params','params','type','type')->>'name')
$sql$ into _res; -- do not work
--EXECUTE ($sql$select ('{"name":"34534534"}'::jsonb)->>'name'$sql$) into
_res; -- work
EXECUTE ($sql$select ('{"name":"ewrewfsf"}'::jsonb)->>'name'$sql$) into
_res; -- do not work
raise notice '%',_res;
END$$;
Hi !
Why i get an error if sends text but not error if send digits ?
ERROR: invalid input syntax for type json
DETAIL: Token "ewrewfsf" is invalid.
CONTEXT: JSON data, line 1: ewrewfsf
PL/pgSQL function inline_code_block line 7 at EXECUTE
SQL state: 22P02