In PrestaShop, the _PS_MODE_DEV_ constant is typically defined in the config/defines.inc.php file, which is located in the root directory of your PrestaShop installation. This constant is used to determine whether your PrestaShop store is in development mode or production mode.
Here’s how it’s typically defined in defines.inc.php:
define('_PS_MODE_DEV_', false);
When _PS_MODE_DEV_ is set to false, it indicates that your PrestaShop store is in production mode, and error reporting may be limited to prevent sensitive information from being displayed to users.
If you want to enable development mode to get more detailed error messages and debugging information, you can set _PS_MODE_DEV_ to true in the same file:
define('_PS_MODE_DEV_', true);
Please note that it’s important to use development mode only for debugging and development purposes. In a production environment, it’s recommended to set _PS_MODE_DEV_ to false to ensure the security and stability of your PrestaShop store.
