I have an ecomm site that has a huge 45% red flag on CLS page speed and I need help with what tags etc to fix it
Competing sites are at 0% or 1% so there is something badly needing fixed.
Please PM me for fuller details and the site
WebPageTest (and Lighthouse) only show CLS during the page load and only under the specific test conditions (device, connectivity, etc). The search console shows CLS collected for the duration of the session while people are on the page, interacting with it (so if things jump while scrolling for example they will show up there but not in testing).
Chaase/Bruce,
You need to watch a slow motion video of the page loading at various viewport sizes to see what is jump down as the page loads. Right away the first thing I notice (common mistake) is the page logo at the top left. Before that loads the nav is shorter in height, after it loads it pushes the whole page down by 40% of the logo height. That’s just one “low hanging fruit” example of the layout shift as individual assets load.