The recommendations below will not only assist with Core Web Vitals but also enhance the overall SEO health of the site.
Custom widgets aren’t always slow to load, but if they require calls to external APIs or 3rd party tools, they may be. Heavy widgets are widgets that, by definition, require external API calls or 3rd party code to load fully. For example, the Map widget, Twitter feed widget, Video widget, any Facebook widget, etc.
Note
The "fold" of a website refers to the portion of the webpage that is visible without scrolling. It's the content you see right away when you first load the page. Anything you have to scroll down to see is considered "below the fold."
Custom and heavy widgets can have different load times from each other, and this can decrease LCP and overall page loading experience.
Tip
For custom widgets, ask your developer to improve how content is rendered and fetched with techniques such as async loading, fetching data off the main thread, and more.
Fonts are automatically downloaded and embedded within the HTML of your page (up to a max of 50KB of fonts), speeding up how fast your browser displays fonts. This helps to prevent CLS and font flashes commonly seen on loading pages.
Tip
Also try to keep the number of weights to a minimum.
Images and background videos are typically the largest asset that browsers download on a site. When there are a lot of images, large images (ones that take up most of the page width) or videos, there can be a delay in LCP and an increase in CLS because the browser has to download the elements before they can be rendered.
If you do need multiple images above the fold, reduce the size of the image to that of an icon or thumbnail.
Tip
Move background videos and slideshows lower on the page. If you want to use a slideshow, limit it to 3 images or less.
Core Web Vitals can have a big impact on how sites are ranked by Google, and promise to do great things for user experience.
For videos, webinar replays and much much more, visit our Core Web Vitals Resource Center, focused entirely on preparing your sites for for Core Web Vitals.