Use our Web Site as External App in Canvas and load in iframe, but won't work ！
I add an app in Edu Center with our web site url，install it in Canvas/Course/assignment/submission select list . It will be loaded in iframe when we preview this assignment. But it can't work well. The iframe is blank, there is nothing. And it log 404 error.
Until now it looks like the wrong way of App Configeration. But I don't konw how to do, because I had did it as the edu app center doc say.