An Azure service that provides an event-driven serverless compute platform.
Hello @Anonymous , Thank you for reaching out.
For Azure Function App there is no option to customize the web.config file. The HTTP request length is limited to 100 MB (104,857,600 bytes), which is true for Version 2.0 as well.
As the request body is getting truncated if it is more than 4 MB I think debugging the function app locally via Visual studio might help in pin-pointing issue faced. You can follow this documentation in order to debug your function app locally via Visual studio.
Please let me know if there are any concerns, I will be glad to continue with our discussion. Thank you!