I believe events aren’t triggered from the iFrame because of the security features, so the microflow won’t execute. If you own the page being shown in the iFrame, and that is part of your application, you could have a datasource microflow on the page in the iFrame that handles your logic. If you don’t own the page being shown on the iFrame I don’t think there is a way for you to know what is happening on that page unless that page is able to message your Mendix application somehow, maybe via a REST service, or JavaScript message.