When using Google PageSpeed Insights, you may receive one or more of these errors:
2. Leverage browser caching: Setting an expiry date or a maximum age in the HTTP headers for static resources instructs the browser to load previously downloaded resources from local disk rather than over the network.
4. Optimize images: Properly formatting and compressing images can save many bytes of data.
While it is possible to resolve issues 1 and 3, it takes extensive custom code modifications due to how Shopify works and handles external resources and is typically not recommended. While the changes can slightly improve your page load times, the cost of changing them compared to the benefits is typically minimal, as outlined in this blog post.
Please note that if you do elect to customize code to resolve issues 1 and 3, this is considered an advanced customization and Out of the Sandbox is unable to provide support or troubleshooting for this process. If you want to move forward with such changes, you will need to hire a third party developer to help.
Once these types of code changes are made to your theme, this also limits how much additional support that Out of the Sandbox can offer in you run into future issues and we may refer you back to your developer to resolve any issues.
Issue 2 cannot be resolved because it requires a change in how the Shopify servers are configured and Shopify is unable to make changes to server configurations.
Issue 4 is one area you can sometimes improve upon by using an image compression tool. There are numerous free and paid resources that you can locate by searching online.