Urgent Performance Issue - Pano loading time is much slower in IE 11 than Chrome and Edge

We have html 5 pano which has serious performance issue on IE11 (tested on Windows 7, 8.1 and 10), attached is profiling of IE11, Chrome and Edge

Any idea why IE11 is much slower than others? the performance of IE is not acceptable and our users are mostly using IE. we need to fix this urgently

Thanks!

No, IE also uses WebGL - see attached right click context menu on the IE pano

yes sure. I'm sending you the link and login by private message. let me know if you have any questions

some further update, we found IE cannot cache the pano images when opening the pano site, so each time the images are downloaded from server which is slower than other browsers which can cache the images locally. We tried open the image url in IE and from the below screenshot (cache_1.jpg) from Fildler we can see the IE can load the image from cache (http status 304), but the image cannot be cached when loading by krpano (cache_2.jpg).

So is there any setting causes krpano always use a no-cache header to request the image url? How can we overwrite this settings?

Thanks