How to debug background/auto update?

Your WP installation must not require FTP credentials on plugins or extensions install.

1. Open wp-content/plugins/unyson/unyson.php and decrease the version

   Important: Decrease only the last digit (third).

   /**
    * ...
    * Version: 2.5.0
    * ...
    */
   

2. Add in {theme}/functions.php

   add_filter( 'auto_update_plugin', '__return_true', 99999 );
   

3. Open phpMyAdmin and delete wp_option named cron. You can run this SQL:

   DELETE FROM `wp_options` WHERE `option_name` LIKE 'cron'
   

4. Open admin page (plugins page) and repeat:

   1. Refresh
   2. Wait 1 second until Unyson will auto-update.

If after 10 refresh nothing happens, run the steps 3. and 4. again.