Annotate a website with the Core Web Vitals
Core Web Vitals Annotations Extension
Two types of annotations will be overlaid onto elements of a webpage:
1. Elements that had layout shift and contributed to the Cumulative Layout Shift score. Depending on the severity of the shift, the annotations will be color coded from lowest impact to highest - yellow -> orange -> dark orange -> red. In the upper left hand corner of each annotation you will find the shift score.
2. The element with the Largest Contentful Paint will be highlighted with a dashed purple annotation. It will include the paint time in the upper left hand corner of the annotation.
The extension popup should open a grid with the FID, LCP and CLS metric timings. At the bottom of the popup is a button to remove the annotations from the website.
Except for the Largest Contentful Paint, the Core Web Vitals metrics are user initiated. Take note of the following when you use the plugin and debug your website:
- The First Input Delay is captured after a user clicks or taps a key on the webpage. If you open the extension before one of those actions, then you will notice that the metric is missing from the grid. To get the First Input Delay, close the extension, make a user action on the page, and then reopen.
- Cumulative Layout Shift is an accumulation of shifts on the page. As you scroll through the page, you may see additional shifts and the extension will add new annotations dynamically. The popup grid that reports the total score will also increase as more shifts accrue.
- Cumulative Layout Shift annotations highlight an element that moved, **not the element that caused the shift**. For example, if an ad loads late on the page, it may push some elements below it downward, causing a shift. The elements below the ad will likely be highlighted, and possibly the ad.
- Given the ad example above, multiple elements on the page may have been shifted after the ad loaded. In that case, only one shift score will be recorded, but all of the affected elements will be highlighted with an annotation. In this case, you should see an arrow (↳) next to the annotated shift score which denotes a grouping of elements that shifted together.
Source Manifest.json
"update_url": "https://clients2.google.com/service/update2/crx",
"description":"Annotate a website with the Core Web Vitals",
"version":"0.0.2",
"name":"Core Web Vitals Annotations",
"permissions":["activeTab"],
"content_security_policy":"style-src 'self' 'unsafe-inline'; script-src 'self' 'unsafe-eval'; object-src 'self';",
"manifest_version":2,
"browser_action":{"default_popup":"popup.html",
"default_icon":{"128":"images/logo-128x128.png"}},
"icons":{"16":"images/logo-16x16.png",
"32":"images/logo-32x32.png",
"48":"images/logo-48x48.png",
"128":"images/logo-128x128.png"}}
How to download and manually install Core Web Vitals Annotations extension for Chrome
Looking for a way to install Core Web Vitals Annotations extensions for Chrome, you can search for them in the Chrome Web Store, clicking the "Add to Chrome" button, and following the straightforward process.
However, you may need to install Core Web Vitals Annotations extensions manually, this article outlines two simple methods to effortlessly install Core Web Vitals Annotations extensions, whether they come as unpacked folders in compressed formats like .zip or as .crx files.
Method 1: Download Core Web Vitals Annotations extension and manually install through Drag &Drop
If you ever need to manually install a Core Web Vitals Annotations extension for Chrome, don't worry, it's a simple process. Just follow these easy steps, and you will have your extension ready to use in no time.
Step 1: Download the Core Web Vitals Annotations Extension by clicking the "Download CRX" button on the website.
Look for the Core Web Vitals Annotations extension you wish to install. Go to the website and download the Core Web Vitals Annotations extension package, which is usually a .CRX file and comes in a zipped file. Here ".crx" file is the format for Core Web Vitals Annotations extension that contains all the data.
Step 2: Extract &Arrange Files
Once the file is downloaded, extract that file into its own folder. Similarly, give that extension files a permanent home. In other words, keep it in a folder that you don't accidentally delete it because these files will be needed to make that extension work.
Step 3: Go to the Chrome Extensions Page
Open Google Chrome and in the address bar, type chrome://extensions; it will open the Google Chrome extensions page. Make sure that "My extensions" is selected in the sidebar.
Step 4: Drag and Drop the Extension
Now, go to the folder where you extracted the Core Web Vitals Annotations extension and drag &drop the extension file from there anywhere onto the extension page within Google Chrome.
Step 5: Complete the Installation
Once you drag and drop the extension file, follow the steps that Google Chrome takes you through. Similarly, if the extension file is of .crx file format, you will be required to review the permissions and then add the extension.
Now, you can manage that added extension as you would like to with any other Chrome extension that you added through Chrome Webstore. Its icon will also appear in the Google Chrome Menu on the right side of the address bar once you activate it.
Method 2: Download Core Web Vitals Annotations extension for Chrome and install in Developer Mode
This is another method to install Core Web Vitals Annotations extension manually, but the twist is that here, you install by enabling the developer mode option provided in Google Chrome. This mode is commonly used for testing extensions or running unpublished tools.
Step 1: Download the Core Web Vitals Annotations extension file
Select and download the Core Web Vitals Annotations extension by clicking the 'Download CRX' button on the website.
Step 2: Extract the downloaded contents
Convert the file to a ZIP file if it is in CRX format then extract the Core Web Vitals Annotations extension zip file or folder that you downloaded. Make sure you extract it using the same folder name and keep it safely in another folder, so you don't delete it by mistake. The extracted folder will be needed to keep your Core Web Vitals Annotations extension running.
Step 3: Open Chrome Extension Setting Page
In the address bar of Google Chrome, type chrome://extensions and open the Chrome Extension Page.
Step 4: Enable Developer Mode
After opening the Chrome Extension page, look at the top right side, and you will find the toggle option of "Developer mode."Simply enable that developer mode option.
Step 5: Load the Unpacked Extension
Once you enable the developer mode option, you will see the menu of Load Unpacked, Pack Extensions and Update. From that, select the option "Load unpacked."
Step 6: Select the Extension Folder
Once the pop-up opens upon clicking Load unpacked, select the Core Web Vitals Annotations extension directory and click on the "Select Folder "button.
Step 7: Confirm and Install
After you select an extension folder of a Google Chrome extension you're installing manually, confirm its installation for the final time and let the installation complete.
Conclusion
Here we've made a step-by-step guide on How to manually install Core Web Vitals Annotations extension in 2 ways. We hope this guide proves helpful.
Similar Extensions
Core Web Vitals 2,000+ 5 ★ 7.29KiB
CLS Visualizer 2,000+ 11 ★ 17.27KiB
Core Web Vitals history 2,000+ 6 ★ 20.6KiB
Checkbot: SEO, Web Speed & Security Tester ? 2,000+ 940 ★ 1.67MiB
LCP & CLS Monitor 2,000+ 1 ★ 19.96KiB
GSC crawl stats downloader 2,000+ 4 ★ 1.78MiB
Core Web Vitals Inspector 2,000+ 0 ★ 357KiB
Core Web Vitals Visualizer 2,000+ 12 ★ 2.39MiB
SpeedVitals 2,000+ 9 ★ 37.18KiB
Web Vitals Tester 2,000+ 1 ★ 1.07MiB
Core SERP Vitals 2,000+ 15 ★ 20.91KiB
AMP Validator 2,000+ 97 ★ 2.51MiB
Web Vitals 2,000+ 43 ★ 398KiB
Schema Builder for Structured Data 2,000+ 29 ★ 889KiB
CLS Checker - Journey Further 2,000+ 9 ★ 107KiB
View Rendered Source 2,000+ 37 ★ 73.68KiB
Ryte structured data helper 2,000+ 16 ★ 373KiB
Robots Exclusion Checker 2,000+ 32 ★ 185KiB
SEO Pro Extension 2,000+ 82 ★ 233KiB
Site Speed by DebugBear 2,000+ 4 ★ 92.18KiB
Google PageSpeed Insights API Extension 2,000+ 38 ★ 101KiB

Dom Size Analyzer 2,000+ 12 ★ 58.04KiB
Hreflang Tag Checker 2,000+ 14 ★ 32.95KiB
DOM-Analyzer 2,000+ 3 ★ 19.52KiB
User reviews
Stian Life (ID: 00000001d058ee5e) Voted 5 ★ - Updated 10/23/2021