In rare circumstances your Cloud app may not resize to the page or it may get stuck "Loading app..."
When this happens refresh/retry. If that does not work then the most likely suspect is a firewall or some problem related to local network topology.
This problem is usually short-lived and transitory. Our recommendation is to refresh/retry. If that does not work then you should suspect your firewall or other network topology is interfering with the loading of all.js from Atlassian. Alternatively, it could be a problem with Atlassian's CDN for delivering all.js.
See the Atlassian task for ACJS-1134 - Investigate all.js CDN reliability
If the problem persists and your network administrator believes that local network issues are not preventing the loading of all.js then contact us via the Artemis Software Support Portal.