I am using the EDB Windows PG 12.1 installer and it seems not to have JIT enabled:
C:\Program Files\PostgreSQL\12\bin>pg_config --configure
--enable-thread-safety --enable-nls --with-ldap --with-openssl --with-ossp-uuid
--with-libxml --with-libxslt --with-icu --with-tcl --with-perl --with-python
Is this expected? Is there a Windows installer available for PG 12 with JIT enabled?