I'm running the latest version of Roundcube [v1.3.8]. The Larry skin is as shipped, so no customization.
I only added $config['product_name'] = 'Moosecraft Webmail, powered by Roundcube'; to './config/config.inc.php'.
Yes, I'm running several plugins:
'archive', 'emoticons', 'enigma', 'filesystem_attachments', 'hide_blockquote', 'identicon', 'identity_select', 'markasjunk', 'newmail_notifier', 'customizr', 'filters', 'carddav', 'virtual_user_mapping', 'rcfilters', 'image_paster', 'html5_notifier', 'message_highlight', 'calendar_notifier', 'contextmenu', 'contextmenu_folder', 'twofactor_gauthenticator'.
My initial thoughts were that it could be an issue with the 'customizr' plugin. Disabling the plugin didn't result in solving the issue.