I’m following the official Salesforce example about Lightning Container Component usage (Released Winter’18 on API 41.0): (RealtyApp)
In the example, I see a manifest.json according to Specifying a CSP Level and no luck, still the same error testing all modes.
Also, I tried with Basic Example as well (GitHub Lightning Container Examples), but I have the same problem.
I’m using a Trailhead Org to test this example but I run out of ideas to figure out what is going on.
At the moment, we don’t know the origin of the problem. We have set a new organization and this component works now.