You'll have to create a simple plugin for that:
1. Create a directory qa-plugin/your-plugin. All the following files go inside this directory
2. Create the file metadata.json with the following content:
{ "name": "Your plugin" }
3. Create the file qa-plugin.php with the following content:
<?php
if (!defined('QA_VERSION')) {
header('Location: ../../');
exit;
}
qa_register_plugin_module('event', 'qa-your-plugin-event.php', 'YourPluginEvent', 'Your Plugin Event');
3. Create the file qa-your-plugin-event.php with the following content
<?php
class YourPluginEvent {
public function process_event($event, $userid, $handle, $cookieid, $params) {
if ($event === 'q_post') {
qa_redirect('');
}
}
}
4. Navigate to admin/plugins and enable the "Your plugin" (remember to click the Save button below the list) event and try asking a question