There is a clash between using WP_DEBUG_DISPLAY and enable_error_logging

[slaFFik]

So, while doing development, in 99% of the cases I set these constants (copied from your .wpsites.php config file that I created while testing the tool):

        "constants" => [
            "WP_ENVIRONMENT_TYPE" => "local",
            "WP_DEVELOPMENT_MODE" => "plugin",
            "WP_DISABLE_FATAL_ERROR_HANDLER" => true,
            "WP_DEBUG" => true,
            "WP_DEBUG_DISPLAY" => true,
            "WP_DEBUG_LOG" => true,
            "SCRIPT_DEBUG" => true,
            "SAVEQUERIES" => true,
            "WP_LANG" => "",
        ],

Unfortunately, the WP_DEBUG_DISPLAY is never set to true because enable_error_logging which is true by default explicitly sets it to false. I think you run enable_error_logging after the defaults.constant are set and effectively overriding the value.

Setting it to "enable_error_logging" => null, behaves the same way as true.

So I it looks like I can't override its behavior, for example, disabling it to do anything with constants.

[andrewjmead]

It looks like there was a bug impacting any custom constants where the value was a boolean. I just fixed it in 1.10.1. Can you give it a try when you get a chance?