Change Log

What is the purpose of the Flash Speed app?

Flash Speed is a Shopify app designed to optimize your store's performance by blocking unused JavaScript files, like those from third-party apps such as Klaviyo, from loading on specific pages where they are not needed. This can improve your store's load time, your Google Pagespeed score, and the overall user experience.

How does the Flash Speed app work?

Flash Speed scans your Shopify store's pages, identifies all JavaScript files loaded, and allows you to block these scripts from loading on specific pages where they are not required. This helps enhance your site's performance by reducing the amount of unnecessary code being loaded.

Is it safe to block JavaScript files using the Flash Speed app?

Yes, blocking unused JavaScript files using Flash Speed is safe. The app does not change anything else on your theme. However, it is recommended to check if the script is really unused as otherwise, some parts of your site might stop working.

Can the Flash Speed app block scripts from any third-party app?

Flash Speed is designed to block unused scripts from various third-party apps. However, some apps might use different methods to load their scripts or have dependencies, which could make it challenging for the app to identify and block them. In case it’s not working on specific scripts, write us an E-Mail at

Will the Flash Speed app affect my store's design or layout?

No, Flash Speed only targets JavaScript files and should not impact your store's design or layout. However, it is always a good practice to test the app on a staging site or with a backup before implementing any changes to ensure it does not impact your store's functionality.

Can I choose which pages to block the unused JavaScript files on?

Yes, Flash Speed provides you with the option to select specific pages where you want to block unused JavaScript files. This allows you to tailor the app's performance optimization to your store's unique requirements.