When i tried to delete cuatom field from the studio it is showing error like " Unable to load widget for 'Proforma_Invoice' : ''"
It could be any warning or deprected messsage from apache. To find the reason check out an apache error log.
Disable display error from your php.ini and try.
Thanks & Regards,
Team Urdhva Tech
Web : http://www.urdhva-tech.com
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