PowerShell RDP session side test script from https://twitter.com/awakecoding/status/1706774232808701978

VerifyIncomfingInput.ps1

Add-Type -TypeDefinition @"
    using System;
    using System.Runtime.InteropServices;

    public struct LASTINPUTINFO {
        public uint cbSize;
        public uint dwTime;
    }

    public class User32 {
        [DllImport("user32.dll", SetLastError = false)]
        public static extern bool GetLastInputInfo(ref LASTINPUTINFO plii);
    }
"@ -Language CSharp

1..100 | % {
    Start-Sleep 1
    $lii = New-Object LASTINPUTINFO
    $lii.cbSize = [System.Runtime.InteropServices.Marshal]::SizeOf($lii)
    [void][User32]::GetLastInputInfo([ref]$lii)
    $LastInputInfoTine = $lii.dwTime
    Write-Host "LastInputInfoTime: $LastInputInfoTime"
}