I have a custom entity with a WebResource on. In the Form Events reference (https://msdn.microsoft.com/en-us/library/gg334481.aspx#BKMK_IFRAMEOnReadyStateCompleteEvent) it lists an IFRAME OnReadyStateComplete event, but I'm unable to determine how to wire this up. I've seen this image:
but I don't have an Events tab in my properties window to choose an event for:
I'm running CRM Online 2015 Update 1