--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/plugins/subscriptions_option/subscriptions_option.php	Thu Jan 04 15:50:29 2018 -0500
@@ -0,0 +1,94 @@
+<?php
+
+/**
+ * Subscription Options
+ *
+ * A plugin which can enable or disable the use of imap subscriptions.
+ * It includes a toggle on the settings page under "Server Settings".
+ * The preference can also be locked
+ *
+ * Add it to the plugins list in config.inc.php to enable the user option
+ * The user option can be hidden and set globally by adding 'use_subscriptions'
+ * to the 'dont_override' configure line:
+ * $config['dont_override'] = array('use_subscriptions');
+ * and then set the global preference
+ * $config['use_subscriptions'] = true; // or false
+ *
+ * Roundcube caches folder lists.  When a user changes this option or visits
+ * their folder list, this cache is refreshed.  If the option is on the
+ * 'dont_override' list and the global option has changed, don't expect
+ * to see the change until the folder list cache is refreshed.
+ *
+ * @author Ziba Scott
+ * @license GNU GPLv3+
+ */
+class subscriptions_option extends rcube_plugin
+{
+    public $task = 'mail|settings';
+
+    function init()
+    {
+        $this->add_texts('localization/', false);
+        $dont_override = rcmail::get_instance()->config->get('dont_override', array());
+        if (!in_array('use_subscriptions', $dont_override)) {
+            $this->add_hook('preferences_list', array($this, 'settings_blocks'));
+            $this->add_hook('preferences_save', array($this, 'save_prefs'));
+        }
+        $this->add_hook('storage_folders', array($this, 'mailboxes_list'));
+        $this->add_hook('folders_list', array($this, 'folders_list'));
+    }
+
+    function settings_blocks($args)
+    {
+        if ($args['section'] == 'server') {
+            $use_subscriptions = rcmail::get_instance()->config->get('use_subscriptions');
+            $field_id = 'rcmfd_use_subscriptions';
+            $checkbox = new html_checkbox(array('name' => '_use_subscriptions', 'id' => $field_id, 'value' => 1));
+
+            $args['blocks']['main']['options']['use_subscriptions'] = array(
+                'title' => html::label($field_id, rcube::Q($this->gettext('useimapsubscriptions'))),
+                'content' => $checkbox->show($use_subscriptions?1:0),
+            );
+        }
+
+        return $args;
+    }
+
+    function save_prefs($args)
+    {
+        if ($args['section'] == 'server') {
+            $rcmail = rcmail::get_instance();
+            $use_subscriptions = $rcmail->config->get('use_subscriptions');
+
+            $args['prefs']['use_subscriptions'] = isset($_POST['_use_subscriptions']);
+
+            // if the use_subscriptions preference changes, flush the folder cache
+            if (($use_subscriptions && !isset($_POST['_use_subscriptions'])) ||
+                (!$use_subscriptions && isset($_POST['_use_subscriptions']))) {
+                    $storage = $rcmail->get_storage();
+                    $storage->clear_cache('mailboxes');
+            }
+        }
+        return $args;
+    }
+
+    function mailboxes_list($args)
+    {
+        $rcmail = rcmail::get_instance();
+        if (!$rcmail->config->get('use_subscriptions', true)) {
+            $args['folders'] = $rcmail->get_storage()->list_folders_direct();
+        }
+        return $args;
+    }
+
+    function folders_list($args)
+    {
+        $rcmail = rcmail::get_instance();
+        if (!$rcmail->config->get('use_subscriptions', true)) {
+            foreach ($args['list'] as $idx => $data) {
+                $args['list'][$idx]['content'] = preg_replace('/<input [^>]+>/', '', $data['content']);
+            }
+        }
+        return $args;
+    }
+}