Image Prioritizer

What the author says it does

This plugin optimizes the loading of images (and videos) with prioritization to improve Largest Contentful Paint (LCP), lazy loading, and more accurate image size selection.

The current optimizations include:

• Add breakpoint-specific fetchpriority=high preload links (both as LINK[rel=preload] elements and Link response headers) for image URLs of LCP elements:
• An IMG element, including the srcset/sizes attributes supplied as imagesrcset/imagesizes on the LINK.
• The first SOURCE element with a type attribute in a PICTURE element. (Art-directed PICTURE elements using media queries are not supported.)
• An element with a CSS background-image inline style attribute.
• An element with a CSS background-image applied with a stylesheet (when the image is from an allowed origin).
• A VIDEO element’s poster image.
• Ensure fetchpriority=high is only added to an IMG when it is the LCP element across all responsive breakpoints.
• Add fetchpriority=low to IMG tags which appear in the initial viewport but are not visible, such as when they are subsequent carousel slides.
• Lazy loading:
• Apply lazy loading to IMG tags based on whether they appear in any breakpoint’s initial viewport.
• Implement lazy loading of CSS background images added via inline style attributes.

The opening of the plugin's own description. The full text, installation notes and changelog are on its WordPress.org page.

Questions the author answers

Latest changelog entry

1.0.0-beta4

Enhancements

• Add declare( strict_types = 1 ) to all PHP files. (2424)
• Bump minimum required WordPress version to 6.9. (2517)
• Bump minimum required PHP version from 7.2 to 7.4. (2469)
• Improve code quality with native property types and stricter static analysis. (1729)

Bug Fixes

• Fix TypeScript 6 type errors in the video lazy-loading script. (2434)