Trying to use the example of a connect addon from here: Bitbucket
Was able to get it connected and at least navigating to the hello-world route, but the iframe never gets sized correctly nor does it think it ever finishes loading the panel. Not exactly sure where to start searching on how to make this work correctly. If I go into inspect console and give the iframe a size it does show as completely loaded, it just is never able to communicate that to the Bitbucket instance for some reason.
Here is a screenshot of what it looks like after I edit it to give the iframe some height.