To improve cumulative layout shift issues, it’s essential to understand what affects CLS in the first place.  Several factors contribute to poor CLS scores, including: Adding videos and images without dimensions Installing ads, iframes, and embeds without dimensions Actions waiting for a page load or network response to update DOM elements (dynamically injected content)Web fonts causing a flash of invisible text (FOIT) or flash of unstyled text (FOUT), slow system fonts, font loading, or a failing font display