User Experience Performance Single Region Diagnostic Results

Webpage: https://www.bostik.com

Device: Desktop Computer

Region: Japan (Tokyo)

Single Region Score

43
Poor Page Performance
A total of 27 improvements can achieve a better score
Properly size images

Serve images that are appropriately-sized to save cellular data and improve load time. [Learn how to size images].

Largest Contentful Paint element

This is the largest contentful element painted within the viewport. [Learn more about the Largest Contentful Paint element]

Eliminate render-blocking resources

Resources are blocking the first paint of your page. Consider delivering critical JS/CSS inline and deferring all non-critical JS/styles. [Learn how to eliminate render-blocking resources].

Minimize main-thread work

Consider reducing the time spent parsing, compiling and executing JS. You may find delivering smaller JS payloads helps with this. [Learn how to minimize main-thread work]

Avoid large layout shifts

These are the largest layout shifts observed on the page. Each table item represents a single layout shift, and shows the element that shifted the most. Below each item are possible root causes that led to the layout shift. Some of these layout shifts may not be included in the CLS metric value due to [windowing]. [Learn how to improve CLS]

Links do not have descriptive text

Descriptive link text helps search engines understand your content. [Learn how to make links more accessible].

Avoid multiple page redirects

Redirects introduce additional delays before the page can be loaded. [Learn how to avoid page redirects].

Layout shift culprits

Layout shifts occur when elements move absent any user interaction. [Investigate the causes of layout shifts], such as elements being added, removed, or their fonts changing as the page loads.

Third parties

Third party code can significantly impact load performance. [Reduce and defer loading of third party code] to prioritize your page's content.

Reduce JavaScript execution time

Consider reducing the time spent parsing, compiling, and executing JS. You may find delivering smaller JS payloads helps with this. [Learn how to reduce Javascript execution time].

Touch targets do not have sufficient size or spacing.

Touch targets with sufficient size and spacing help users who may have difficulty targeting small controls to activate the targets. [Learn more about touch targets].

Serve images in next-gen formats

Image formats like WebP and AVIF often provide better compression than PNG or JPEG, which means faster downloads and less data consumption. [Learn more about modern image formats].

Improve image delivery

Reducing the download time of images can improve the perceived load time of the page and LCP. [Learn more about optimizing image size]

LCP request discovery

Optimize LCP by making the LCP image [discoverable] from the HTML immediately, and [avoiding lazy-loading]

Avoid serving legacy JavaScript to modern browsers

Polyfills and transforms enable legacy browsers to use new JavaScript features. However, many aren't necessary for modern browsers. For your bundled JavaScript, adopt a modern script deployment strategy using [module/nomodule feature detection] to reduce the amount of code shipped to modern browsers, while retaining support for legacy browsers. [Learn how to serve modern JavaScript]

Displays images with incorrect aspect ratio

Image display dimensions should match natural aspect ratio. [Learn more about image aspect ratio].

Defer offscreen images

Consider lazy-loading offscreen and hidden images after all critical resources have finished loading to lower time to interactive. [Learn how to defer offscreen images].

Reduce unused CSS

Reduce unused rules from stylesheets and defer CSS not used for above-the-fold content to decrease bytes consumed by network activity. [Learn how to reduce unused CSS].

Render blocking requests

Requests are blocking the page's initial render, which may delay LCP. [Deferring or inlining] can move these network requests out of the critical path.

Efficiently encode images

Optimized images load faster and consume less cellular data. [Learn how to efficiently encode images].

Browser errors were logged to the console

Errors logged to the console indicate unresolved problems. They can come from network request failures and other browser concerns. [Learn more about this errors in console diagnostic audit]

Missing source maps for large first-party JavaScript

Source maps translate minified code to the original source code. This helps developers debug in production. In addition, Lighthouse is able to provide further insights. Consider deploying source maps to take advantage of these benefits. [Learn more about source maps].

Uses deprecated APIs

Deprecated APIs will eventually be removed from the browser. [Learn more about deprecated APIs].

Background and foreground colors do not have a sufficient contrast ratio.

Low-contrast text is difficult or impossible for many users to read. [Learn how to provide sufficient color contrast].

Document request latency

Your first network request is the most important. Reduce its latency by avoiding redirects, ensuring a fast server response, and enabling text compression.

Reduce the impact of third-party code

Third-party code can significantly impact load performance. Limit the number of redundant third-party providers and try to load third-party code after your page has primarily finished loading. [Learn how to minimize third-party impact].

Reduce unused JavaScript

Reduce unused JavaScript and defer loading scripts until they are required to decrease bytes consumed by network activity. [Learn how to reduce unused JavaScript].

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