I posted this issue https://www.devexpress.com/Support/Center/Question/Details/T812285/intermittent-webdocumentviewer-issues-in-azure-the-red-message-displaying-internal a couple of weeks ago, originally we thought we had a solution by setting the maxAllowedContentLength but the problem was inadvertently fix when we added the setting in the web.config the environment variable ASPNETCORE_ENVIRONMENT = Development was also added (incorrectly) and deployed.
Once this was discovered and we removed the environment variable we went back to having intermittent issues which relate to the size of the data. If we run our solution locally and simply toggle the environment variable setting we can replicate it; production it fails development it works. We tracked down this ticket https://www.devexpress.com/Support/Center/Question/Details/T684507/net-core-report-does-not-show-in-production-environment we took the sample project supplied upgraded it to .net core 3.0 hard coded a large amount of data and we got the error setting the environment variable to development and it goes away. Doing the same steps in the sample project but without upgrading to .net core 3.0 and we didnt get the error.
I have attached two projects the .net core 3.0 project with the hardcoded data where we got the error and the .net core 2 project where we didnt get the error, I have also attached a screenshot of the error we were seeing. It appears the conditions for the bug to happen are:
.net core 3.0
ASPNETCORE_ENVIRONMENT = Production
Large amount of data
P.S I was unsure if I should amend my original ticket as I had incorrectly marked it as solved.
It looks like this issue is more related to your ASP.NET Core application configuration, rather then to our components. This is because your application limits the size of the response that is returned to the browsers, so our client-side code fails to parse the JSON data that was returned by the web server. In any case, I checked your project and found that the "IIS Express" profile of your application is hosted on IIS Express and the "WebApplication9" profile launches Kestrel. The web.config is ignored by Kestrel, this is why your solution does not work for this kind of environment. You need to use the Limits property of the KestrelServerOptions class to enlarge the limits for Kestrel. Check the How to increase file upload size in ASP.NET Core article for more information regarding this.