Hope you all are doing well.
If you want to disable the theme and plugin file editor from admin then don’t worry, i am here only for you :)
add the give code below in wp-config file.
Basically this is very important for make your site more secure because generally most of people have used their UN-secure admin password , they have used password like “admin123”, “admin”,”admin@123″ and site hacker can easily your hack your admin password.
After hack the admin access he can changes anything in theme files as well plugin files also and after done anything by hacker in files your site will be down. So don’t waste your time just add this code in your wp-config.php files
define( 'DISALLOW_FILE_EDIT', true );