Hello HansR!
We appreciate you reaching out to us!
Well, when I opened the demo everything is working fine, the image is shown as the background of the chart. I am attaching a screenshot:
- setting-a-plot-backgroun.jpeg (54.54 KiB) Viewed 616 times
This is an official demo and it is working correctly also on my colleague's computers.
Do you have any errors in your console? Maybe you have some blockades in your browser or your antivirus program blocks some URLs? I suggest checking the chart also on other browsers. It is not looking, like a Highcharts problem, but maybe together we will find a solution. Also, can you try to export the image of the chart and check if there is a background image?
I am looking for your response.
Regards!