After reading your post I was curious because I had never heard of Dump1090-OpenLayers3-html. I downloaded the files, replaced my current /usr/share/skyaware/html with the files from Al Kissack and it worked right out of the box. I hadn’t opened Skyaware on this browser today and I always have my browser delete cookies and cache when I exit.
Check this thread. It has more instructions and someone there had a similar issue as you do. I hope that helps.
