Native Lazyload

Description

Lazy-loads media using the native browser feature. Learn more about the new loading attribute or view the WordPress core ticket where inclusion of a similar implementation in WordPress core itself is being discussed.

If the loading attribute is not supported by the browser, the plugin falls back to a JavaScript solution based on IntersectionObserver. For the case that JavaScript is disabled, but the loading attribute is supported by the browser, a noscript variant of the respective element will be added that also includes the loading attribute without any further changes.

“Native” means “Fast”

If you have found your way over here, you are probably aware of how crucial performance is for a website’s user experience and success. You might also know that lazy-loading is a key feature to improve said performance. However, the solutions for lazy-loading so far still added a bit of overhead themselves, since they relied on loading, parsing and running custom JavaScript logic, that may be more or less heavy on performance.

This plugin largely does away with this pattern. It relies on the new loading attribute, which makes lazy-loading a native browser functionality. The attribute is already supported by Chrome, and will be rolled out to other browsers over time. The solution being “native” means that it does not rely on custom JavaScript logic, and thus is more lightweight. And “more lightweight” means “faster”.

Last but not least, a neat thing to keep in mind is that this plugin will essentially improve itself over time, as more browsers roll out support for the loading attribute.

Usage

Just activate the plugin, and all your images and iframes in post content will be loaded lazily.

Credit

This plugin is partly based on logic from WP Rig as well as recommendations from web.dev and developers.google.com.

Installation

1. Upload the entire native-lazyload folder to the /wp-content/plugins/ directory or download it through the WordPress backend.
2. Activate the plugin through the ‘Plugins’ menu in WordPress.

FAQ

Where are the plugin’s settings?

This plugin does not have a settings screen. Just by activating it, the plugin will work.

How can I prevent an image or iframe from being loaded lazily?

You can add a class skip-lazy to indicate to the plugin you would like to skip lazy-loading for this image or iframe.

This plugin still loads an extra JavaScript file! I don’t want that.

This is perfectly fair. Note that the plugin only loads the JavaScript file as a fallback for when the user’s browser does not support the native loading attribute yet. The file includes logic to still autoload the image in a non-native way. If you prefer to purely rely on the loading attribute and not provide any fallback, you can easily disable it by adding a line add_filter( 'native_lazyload_fallback_script_enabled', '__return_false' ) somewhere in your site’s codebase.

Does this work with AMP?

If you use AMP, you don’t actually need this, since AMP intelligently lazy-loads media out of the box. Still, the plugin is built in a way that it will not break AMP compatibility, just to make sure.

Where should I submit my support request?

For regular support requests, please use the www.remarpro.com support forums. If you have a technical issue with the plugin where you already have more insight on how to fix it, you can also open an issue on Github instead.

How can I contribute to the plugin?

If you have some ideas to improve the plugin or to solve a bug, feel free to raise an issue or submit a pull request in the Github repository for the plugin. Please stick to the contributing guidelines.

You can also contribute to the plugin by translating it. Simply visit translate.www.remarpro.com to get started.

Reviews

It lazy loads my popups

othman19 July 26, 2022

How can I unable the lazy loading of my popups ?

Google update your products PLEASE

NikosTsolakos February 17, 2022

Im really happy that Google is creating plugins for our projects BUT keep them up-to-date please… you’re the God of the internet, a trillion dollar company.

Native lazy loading – the only viable lazy loading solution

bloup December 31, 2020

This plugin adds loading=”lazy” and then, the browser lazy loads the image. I think that native lazy loading performed by the browser is the only viable solution for lazy loading. For many years, I tried to implement lazy loading on my websites. I faced many issues. Once images were not crawled. Once my website was penalized because of cloaking. Versions differed depending on the client. I am enough with javascript scripts that slow down the pageload and negatively impact the pagespeed insight. I think that for now and in the future, the native lazy loading is the only way to go for lazy loading.

Broken on safari

gkwebph August 13, 2020

Hey guys – Can you please fix this in the latest Safari. Thanks!

It does not improve my sites

havig February 27, 2020

First, did not break my site and it did lazyload most of the page images. It does not lazyload images if they are served from a different host. Example, unbounce, etc. I will add another caveat, all of my images and their versions are always carefully resized and highly compressed. Checked with lighthouse and my score took a hit downwards. 13 points down on performance score. I tested on my Staging area, uncached. FCP went from 2.1s to 4.2s, all of the other metrics, including time to interactive, CPU idle, speed index and First Meaningful Paint took a dive. I will chuck this to I was already hyperoptimized and lazy loading is not truly needed on my site/s. But I would advise others to try it out (not on their live site) and test speed with Google Lighthouse before and after.

Does what it says

shawn caza February 17, 2020

Seems to work well. On browsers that don’t support lazy loading, it doesn’t seem to load the images as soon as I would like. As in there can be a bit of a delay between scrolling and the image appearing on screen. Not to bad though. Not going to worry about it as native image loading is the way of the future and will be implemented into more browsers.

Contributors & Developers

Changelog

1.0.2

• Fix broken images which are using data URI scheme (e.g. base64-encoded images). Props ieim.
• Fix images in IE 11 not being loaded until the user starts scrolling. Props Soean.
• Fix image loading script not working in IE10 and other browsers that do not support dataset.

1.0.1

• Improve compatibility with other plugins by using more specific class and only adding it for JS fallback.
• Run lazy-load script on DOMContentLoaded when necessary to improve compatibility with plugins like Autoptimize.
• Do not transform elements inside an AJAX response due to lack of predictability of the context and script execution.

1.0.0

• Initial release