diff --git a/dev/TODO.md b/dev/TODO.md
index 73ff2cea5..6431cd3bc 100644
--- a/dev/TODO.md
+++ b/dev/TODO.md
@@ -14,3 +14,9 @@
   "Generating static pages" time (locally 6.6s with them, 3.6s without).
   Options: hoist the font and logo reads in `src/app/api/og/[...path]/route.tsx`
   to module scope, or render one image per top-level section instead of per page
+- Serve MDX screenshots as WebP through `/_next/image`: branch
+  `marc/perf/webp-images` (split out of #1975) routes allow-listed GCS
+  PNG/JPEGs through Next's image optimizer, 1214 KB → 214 KB on
+  `/batch-changes/delete-a-batch-change`. Needs a decision on the Vercel
+  Image Optimization bill (~360 source images, one transform per week per
+  region) before it goes up as a PR
diff --git a/src/components/mdx/ZoomableImage.tsx b/src/components/mdx/ZoomableImage.tsx
index ef395215c..1ad752aea 100644
--- a/src/components/mdx/ZoomableImage.tsx
+++ b/src/components/mdx/ZoomableImage.tsx
@@ -32,6 +32,7 @@ export function ZoomableImage({className, alt, ...props}: ZoomableImageProps) {
 			<img
 				className={`cursor-zoom-in rounded-xl ${className ?? ''}`}
 				alt={alt}
+				loading="lazy"
 				onClick={openModal}
 				{...props}
 			/>