Image preload causing duplicate downloads on mobile

  • rbabt

    (@rbabt)


    2 days, 12 hours ago

    I think there is an issue with the LCP image preload.

    The preload uses the image size selected in WordPress. For example if you select Large it will put the 1024 version into the preload:

    <link rel="preload" fetchpriority="high" as="image" href="...1024x768.png.webp">

    But the actual image uses a responsive srcset, so on mobile it may then select a smaller image instead. This means the larger image may be downloaded first, followed by the smaller image, resulting in the image being downloaded twice on the device where we’re supposed to be minimising image sizes!

    Could the preload use the same responsive image selection as the actual image, for example:

    <link rel="preload" fetchpriority="high" as="image"
          imagesrcset="...300x225.png.webp 300w, ...768x576.png.webp 768w, ...1024x768.png.webp 1024w">

    rather than always preloading the image size selected in WordPress?

    Relevant link: https://html.spec.whatwg.org/#attr-link-imagesrcset

Viewing 1 replies (of 1 total)
  • Plugin Support qtwrk

    (@qtwrk)

    1 day, 9 hours ago

    this is more like a feature/improvement request, I will forward it to our dev

Viewing 1 replies (of 1 total)

You must be logged in to reply to this topic.