I've been trying to increase the speed score on my online store and have done everything I can now to reduce the download time.
We are using the Brooklyn theme - does anyone know if it is common with the Brooklyn theme to have a low speed score. I have reduced all image and file sizes and not sure what else to do.
Our store is:
Any suggestions would be appreciated!
Reducing unused JS and CSS is good if you have extra files loading that you don't use (like from old apps that you deleted but didn't remove the theme code)... but as for extracting unused CSS and JS out of files you do use, that's a large project with tiny gains so I wouldn't recommend that.
To see what can and should be optimized on a Shopify site, check the Shopify Analyzer. It's a free performance analysis tool my team built for the Shopify community. That will show you what can be optimized + give recommendations.
If the recommendations are outside the expertise of your team, just contact us from there and we'll get you dialed in.
but as for extracting unused CSS and JS out of files you do use, that's a large project with tiny gains so I wouldn't recommend that.
Not only that, if people start to do things like switching to inline CSS (recommended on the developer tools linked from the speed score page) it can cause major problems.
And that's only part of the issue with Speed Score. Shopify gets everyone all worked up about this metric, then when we dig into the details discover that it's JS and CSS files, many associated with Shopify itself, or sometimes mission-critical apps or services that will cause more harm than good if we turn them off to get an incremental improvement on the speed score.
These issues should be addressed in the explainer text right on the Shopify admin page where Speed Score is listed, as well as in tooltips in key places where store owners might cause a problem, such as selecting slideshows (bad) instead of a single image of a reduced size (good). Here are some other ideas: flagging script- and process-heavy apps in the app store before people install them, and fixing Shopify's free themes that link to giant JS files.
Bottom line, I think Shopify is doing the right thing by warning us about speed issues, but the ways they let us know leave a lot to be desired and more could be done to proactively prevent Speed issues.