This is an old revision of the document!
PageSpeed Insights Zero Score
PrestaShop's internal cache may lead to a zero PageSpeed Insights score.
Example
After LiteSpeed Cache for PrestaShop is enabled, you see a very fast loading speed (464ms) for TTFB through the browser. Also Gtmetrix and Pingdom show good results. However Google's PageSpeed Insights consistently gives a 0 result.
Google states:
Lighthouse returns a Performance score between 0 and 100. 0 is the lowest possible score. A 0 score usually indicates an error in Lighthouse. If you see a 0 score repeatedly, please file a bug on the Lighthouse repo.
Lighthouse seems to be having difficulty with your PrestaShop site.
Solution
PrestaShop has an internal cache, Smarty Cache, which may lead to this zero PageSpeed Insights score. It has nothing to do with LiteSpeed Cache for PrestaShop. If you clear PrestaShop's internal cache then everything should be fine.
Navigate to PrestaShop Admin > Advanced Parameters > Performance and press the Clear cache button.
