Our web app is running in .Net Framework 4.0. The UI calls controller methods through ajax calls.
We need to consume REST service from our vendor. I am evaluating
It's important to evaluate the different ways you can create an HttpClient, and part of that is understanding HttpClientFactory.
https://docs.microsoft.com/en-us/dotnet/architecture/microservices/implement-resilient-applications/use-httpclientfactory-to-implement-resilient-http-requests
This is not a direct answer I know - but you're better off starting here than ending up with new HttpClient(...)
everywhere.