Performance improvement proposal (core and support level changes)

[tunyk]

I propose to implement this in the basic WordPress functions so that they can be simply activated or not activated (with checkboxes in the settings section):

Intersection Observer API
Mutation Observer API
Speculative Loading (integrate the functionality of this plugin into the basic system – ​https://wordpress.org/plugins/speculation-rules/)
PWA – (integrate the functionality of this plugin into the basic system – ​https://wordpress.org/plugins/pwa/)
Use CSS content-visibility in standard WordPress themes ​https://web.dev/blog/css-content-visibility-baseline

PS. This will allow us to use fewer plugins and your own code, speed up site loading, improve security

[swissspidy]

Hi there,

You might be interested in learning about the ​WordPress core performance team, which is dedicated to monitoring, enhancing, and promoting performance in WordPress core and its surrounding ecosystem. That includes working with some of the technologies you are listing here.

Typically we create separate tickets either here on Trac or on ​https://github.com/WordPress/performance for each individual feature the team is working on, rather than having one catch-all ticket.

Intersection Observer API
Mutation Observer API

Here, you are just listing some technologies that by itself don't do much. They're just a means to an end. So this is not really actionable.

Speculative Loading (integrate the functionality of this plugin into the basic system – ​https://wordpress.org/plugins/speculation-rules/)

Integrating the functionality of that plugin into core is actually the whole point of its existence. It's a so-called feature plugin that allows us to test and refine features before merging into WordPress itself.

Speculative loading integration is already being worked on in #62503, targeting 6.8.

PWA – (integrate the functionality of this plugin into the basic system – ​https://wordpress.org/plugins/pwa/)

Same for this plugin :-) While it works great on its own, it was also originally built to be integrated into core itself. It's even in the readme.

Use CSS content-visibility in standard WordPress themes ​https://web.dev/blog/css-content-visibility-baseline

Again, a means to an end. It's not something you just add everywhere to make performance better.

content-visibility is being looked at in ​https://github.com/WordPress/performance/issues/1308.

[westonruter]

Intersection Observer API

Also, this is being used extensively in the ​Optimization Detective plugin (with its extensions ​Image Prioritizer and ​Embed Optimizer). These are feature plugins intended for eventual proposal for core merge.

The Performance ​issue for content-visibility is also for Optimization Detective.

[tunyk]

When I write about these points, I mean using them for lazy loading - the so-called skeletons. loading="lazy" is not enough.

The combined use of the Intersection Observer API and Mutation Observer API, as well as CSS content-visibility + prioritization is the best solution