
add_users capability
The only place where you can find ‘add_users’ WordPress user capability in WordPress source code is
/wp-admin/includes/schema.php:
781 | $role->add_cap( 'add_users' ); |

add_users capability
The only place where you can find ‘add_users’ WordPress user capability in WordPress source code is
/wp-admin/includes/schema.php:
781 | $role->add_cap( 'add_users' ); |

User Role Editor v. 3.4


User Role Editor 3.3


activate_plugins
activate_plugins capability on the top of the mountain really gives user access to “Plugins” and “Installed Plugins” menu items of WordPress admin back-end menu system and lets him activate/deactivate plugins one by one or applying bulk action to the set of selected plugins.



Custom User Roles
One example of lost WordPress functionality for custom user role is described here:
