Why Does My Preview Feel Slow?

If you're opening your preview and it feels slow, this is normal. There are a couple reasons this happens:

• When you visit your site, your browser already has the images and other assets cached since you've probably visited it before. These assets have to be downloaded again in the browser.
• As the preview is new, Shopify hasn't cached it on the server yet. 
• Shopify injects some extra scripts in every preview to display the preview bar at the bottom. These scripts are quite large.