Line graph rendering as a single horizontal line when deployed to server

[AndyFro]

The AJAX Control Toolkit <VERSION>

18.1.0.0

The installation method

Download and install from DevExpress to get AjaxControlToolkit.dll, placed on same directory as bin files.

Minimal steps to reproduce the bug

Line Graph renders as expected on developer machine (see below) but as a horizontal line on the server.

This is a simple test that loads an aspx page containing the demo code for a line graph copied and pasted from http://www.ajaxcontroltoolkit.net/LineChart/LineChart.aspx
There is no code behind except an empty Page_Load.

This is deployed to a GoDaddy server running Windows Server 2019 Standard with the Trust Level set at Full.

Actual result

seen on server...

Expected result

seen on development machine...

Browser(s) used

Google Chrome
Mozilla FireFox
Microsoft Edge
same result on each browser

A site deployment method

IIS

Complete aspx page

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="TestGraph.aspx.cs" Inherits="Application.TestGraph" %>

<%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="AjaxToolkit" %>

<title></title>

<asp:ScriptManager ID="ScriptManager" runat="server" EnablePageMethods="true" /> 

<ajaxToolkit:LineChart ID="LineChart1" runat="server" 
ChartWidth="450" ChartHeight="300" ChartType="Basic" 
ChartTitle="United States versus European Widget Production" 
CategoriesAxis="2007,2008,2009,2010,2011,2012" 
ChartTitleColor="#0E426C" CategoryAxisLineColor="#D08AD9" 
ValueAxisLineColor="#D08AD9" BaseLineColor="#A156AB">
<Series>
    <ajaxToolkit:LineChartSeries Name="United States" 
    LineColor="#6C1E83" Data="110, 189, 255, 95, 107, 140" />
    <ajaxToolkit:LineChartSeries Name="Europe"  
    LineColor="#D08AD9" Data="49, 77, 95, 68, 70, 79" />
</Series>
</ajaxToolkit:LineChart>

</form>

Tags referencing AjaxToolkit that are common to both development machine and Web.Config on server

<system.web>

<compilation debug="true" targetFramework="4.0" defaultLanguage="c#" tempDirectory="C:\Inetpub\vhosts\Application.mine.nu\tmp" >
  <assemblies>
    <add assembly="AjaxControlToolkit"/>
  </assemblies>
</compilation>

<pages>
  <controls>
    <add assembly="AjaxControlToolkit" namespace="AjaxControlToolkit" tagPrefix="ajaxToolkit"/>
  </controls>
</pages>

</system.web>