Are you getting a WordPress error that says “Allowed Memory Size Exhausted”?
Can not open Customizer?
This is one of the most popular WordPress errors. Though it is simple to increase the WordPress memory limit in just a few steps.
1. Edit your wp-config.php file and enter something like:
WordPress memory can be different to the server – you need to set this regardless of server memory settings
2. If you have access to your PHP.ini file, change the line in PHP.ini
If your line shows 32M try 64M or better 128M:
memory_limit = 64M;
3. If you don’t have access to PHP.ini try adding this to an .htaccess file:
php_value memory_limit 128M
Contact your host
If this solution does not work for you, then this means your web hosting service provider does not allow WordPress to increase PHP memory limit. You will need to ask your web hosting provider to increase your PHP memory limit manually.