X instead of the circle icon widget on first load / leverage

I use Vantage theme and I use the circle icon widget on my site but on the first load, it displays only a boxed X for most of the time. I discovered that the Leverage Browser Caching plugin caused this problem. But if I turn this plugin off, the page loading speed increases much, especially on mobile browsers. Is there a way, to load very fast and use all the features of the Vantage theme? Which plugins and settings are recommended by you? I appreciate your help. My site: https://manojuggling.com