We use the turbo theme and until not too long ago several icons the theme provides (shopping cart icon, search icon, but also all social media icons) are broken. Instead of showing the actual icon, it simply shows the (for example) \ea96 code in a square. While we did change the font of the body with CSS, this shouldn't be the problem as it broke at a later time. I've compared the icons' CSS of the icons on our site and that of several sites including the demo site for the portland version of the theme with our icon:before CSS class and it is identical. On those sites the icons show correctly, on ours they don't. I've also tried to undo the font changes on the website but that didn't help either. I'm wondering if anyone could help identifying the problem.
You can find our site at https://www.zendro.nl and either check the header or any product page to see the missing icons.
Julie here from Shopify Support.
This definitely sounds like this is a theme-related issue. In this case, I suggest contacting the theme developers directly. Third-party themes are structured quite a bit differently than Shopify-developed themes, so seeking assistance from the developers will be your best course of action; they know their code inside and out.
The Turbo theme isn't available in the Shopify Theme Store, but I did manage to find it on Out of the Sandbox's website. You should be able to get in touch with the developers through the contact page on their site, or through the Help widget. We also have a help doc on where to find support for your theme that should help!
Another way to get help with third-party themes is to hire a Shopify Expert. Since Shopify Experts are highly skilled in web development, they should be able to examine your theme's code and pinpoint the issue.
I'm also curious to know if anyone in the Shopify Community has some suggestions on how to resolve this issue!