Hi @GrasshopperGeo ,
Apologies for the delay in getting back to you and thanks for your question!
While do recommend Google Chrome for best results, Shopify is compatible with all browsers, so long as they are up to date - so be sure to upgrade your browser if it needs to be upgraded. Be sure too to upgrade your operating system on any device you are using.
You mentioned that you are using a third-party theme called Expanse which may account for why your social icons do not display in some browsers. Have you reached out to Expanse Theme support?