Select all that apply. Which of the following can negatively impact your CLS score?
- Images and iframes without inline dimensions
- Large items like YouTube video embeds or image sliders
- Dynamically injected content
- Improperly loaded custom webfonts
Explanation: The correct answers are Images and iframes without inline dimensions, Dynamically injected content, and Improperly loaded custom webfonts. Cumulative Layout Shift (CLS) measures the visual stability of a webpage by quantifying how much its content shifts during the loading process. Elements such as images and iframes without specified dimensions can cause layout shifts because the browser needs to allocate space for these elements once they load, leading to unexpected content movement. Similarly, dynamically injected content, such as ads or pop-ups loading after the initial render, can disrupt the layout and trigger layout shifts. Moreover, improperly loaded custom web fonts can also negatively impact CLS, especially if the browser initially renders text using default fonts before swapping them out for custom ones, resulting in noticeable layout shifts. Large items like YouTube video embeds or image sliders can contribute to poor CLS if they cause sudden and significant changes to the page layout upon loading. By addressing these factors and optimizing the loading behavior of web elements, website owners can improve their CLS scores, enhance user experience, and potentially boost their search engine rankings.