core(uses-responsive-images-snapshot): ignore CSS images (#14890)

GoogleChrome · Mar 21, 2023 · 947366d · 947366d
1 parent db62a55
commit 947366d
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/core/audits/byte-efficiency/uses-responsive-images-snapshot.js b/core/audits/byte-efficiency/uses-responsive-images-snapshot.js
@@ -56,6 +56,10 @@ class UsesResponsiveImagesSnapshot extends Audit {
     /** @type {LH.Audit.Details.TableItem[]} */
     const items = [];
     for (const image of artifacts.ImageElements) {
+      // Ignore CSS images because it's difficult to determine what is a spritesheet,
+      // and the reward-to-effort ratio for responsive CSS images is quite low https://css-tricks.com/responsive-images-css/.
+      if (image.isCss) continue;
+
       if (!image.naturalDimensions) continue;
       const actual = image.naturalDimensions;
       const displayed = UsesResponsiveImages.default.getDisplayedDimensions(