ERR_HTTP2_INADEQUATE_TRANSPORT_SECURITY when accessing PowerShell Universal

ERR_HTTP2_INADEQUATE_TRANSPORT_SECURITY when accessing PowerShell Universal

When accessing PowerShell Universal with a Chromium-based browser such as Google Chrome or Microsoft Edge, you can encounter an error when HTTPS is enabled. The error will state ERR_HTTP2_INADEQUATE_TRANSPORT_SECURITY. 
Root Cause:
The reason for this issue is because the operating system you are using does not support HTTP2. By default, PowerShell Universal will serve both HTTP1 and HTTP2 while favoring HTTP2. If you are running on an operating system, like Windows Server 2012R2, that does not support HTTP2, you will see this error in the browser.
To work around this issue, you can either run PowerShell Universal on an operating system that supports HTTP2 or you can turn off HTTP2 support in your appsettings.json file. 
To learn about turning off HTTP2 support, see our documentation:
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