/plugins/managesieve/config.inc.php
// Disabled actions. Prevents user from performing specific actions by disabling
// the UI elements:
// - list_sets,
// Note: disabling list_sets removes the Filter sets widget from the UI and means
// the set defined in managesieve_script_name will always be used (and activated)
// - enable_disable_set,
// - delete_set,
// - new_set,
// - download_set,
// - new_filter,
// - delete_filter,
// - redirect: This one will remove 'redirect' option from the filter actions selector
// Note: This will not remove it for redirect actions already existing in the script.
// Note: This has no impact on the Forwarding UI
$config['managesieve_disabled_actions'] = [];
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