krpano set base64 img for hotspot.url, not work on ios's browsers

Question

but work for pc's browser, and android's.

addhotspot(newspot);
<!-- set(hotspot[newspot].url,"./assets/sun.png"); -->
set(hotspot[newspot].url,"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAACAAAAAgAQMAAABJtOi3AAAAA1BMVEW+CAiuuOz6AAAAC0lEQVQI12MY5AAAAKAAAfgHMzoAAAAASUVORK5CYII=");
set(hotspot[newspot].ath,-180);
set(hotspot[newspot].atv,-90);
set(hotspot[newspot].width,100);
set(hotspot[newspot].height,100);
set(hotspot[newspot].alpha,.05);

help! TKS!