Until 15 days ago I embed the CDF file on this site and made good use of it.
The inserted source is as follows.
However, the CDF file embedded in the web page from a few days ago is not a plug-in. I did not modify this web page.
In any case, I tested it at http://demonstrations.wolfram.com and confirmed that the site was plugged in and working properly.
My work environment is Windows 7, 64 bit, Explorer 11, and Mathematica and Wolfram CDF Player 11.1 are installed.
I would like to know why suddenly things that have worked well in the past, such as the above script, have been inserted into a web page.