It looks like you are using ACE but, if the all.js file is not being loaded into your iframe then the Javascript bridge will never be established between the host product and your iframe and that message will eventually show up. The symptoms would match.
In our case, we’ve all of that panels that show our content but then also show the spinner with “Loading app…” and eventually “App is not responding” on an issue load.
However…
It only happens in one particular issue view context (filter view on left, issue on right). When just opening an issue, everything is fine. And if you reload the page, everything is fine. Here’s a video from one of our test instances.
all.js is being loaded everywhere.
Our Cloud app is 1.5 years old and fairly widely used. I don’t think this was happening before.
We haven’t opened a ticket yet in ACJIRA as we’re still investigating. I was searching for an ACJIRA ticket today when I came across this forum posting above that sort of sounded like what we’re seeing.
@rmassaioli
We did some more investigation today and I want to put the results here for others to see.
Here’s some notes from my lead UI dev:
When an IFrame is loaded it wants to know where it’s loaded. That’s why it calls this Atlassian API: AP.getLocation.
Jira accidentally inserts two our IFrames but their JS connects only to one of them. That’s why it cannot detect that other IFrame is loaded and shows spinner, also it cannot respond to JS API calls like AP.getLocation.
This screenshot of Jira layout relates to the problem: Monosnap
I’m using the NodeJS framework. Including the handlebar layout solved the issue. Inside the layout handlebar all.js is loaded. So you are probably right.
In case it helps, we recently had same issue, also related with the loading of all.js file.
Following the steps here, in step 2 the example for the HBS view includes the statement to import all.js from https://ac-getting-started.atlassian.net/atlassian-connect/all.js, but loading of this file was failing, apparently due to a mismatch with the MIME type and the actual file content.
Checking on the web console of the browser while loading the JIRA page we noticed that all.js was also loading from https://connect-cdn.atl-paas.net/all.js, so using this URI in the HBS statement solved the issue.