Version 3.4 Triggered Error

In addition to attached error log, the Site Title does not translate but the page content does. Reverted to v 3.3.3

Error Details

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An error of type E_ERROR was caused in line 81 of the file /var/www/wp-content/plugins/polylang/admin/admin-base.php. Error message: Uncaught Error: Call to undefined method PLL_Model::set_languages_ready() in /var/www/wp-content/plugins/polylang/admin/admin-base.php:81

Stack trace:

#0 /var/www/wp-content/plugins/polylang/admin/admin.php(72): PLL_Admin_Base->__construct(Object(PLL_Links_Directory))

#1 /var/www/wp-content/plugins/polylang/include/class-polylang.php(230): PLL_Admin->__construct(Object(PLL_Links_Directory))

#2 /var/www/wp-includes/class-wp-hook.php(308): Polylang->init('')

#3 /var/www/wp-includes/class-wp-hook.php(332): WP_Hook->apply_filters(NULL, Array)

#4 /var/www/wp-includes/plugin.php(517): WP_Hook->do_action(Array)

#5 /var/www/wp-settings.php(486): do_action('plugins_loaded')

#6 /var/www/wp-config.php(102): require_once('/var/www/wp-set...')

#7 /var/www/wp-load.php(50): require_once('/var/www/wp-con...')

#8 /var/www/wp-admin/admin.php(34): require_once('/var/www/wp-loa...')

#9 /var/www/wp-admin/update.php(16): require_once('/var/www/wp-adm...')

#10 {main}

  thrown