ROOT CAUSE: Articles from sites like onemileatatime.com serve WebP
images with .jpeg extensions. WebKit attempts JPEG decode, fails,
retries as WebP — the retry loop blocks the compositor thread during
scroll, causing ~1s freezes per image.
FIX 1 — Image attributes (ArticleHTMLBuilder.optimizeImages):
Regex injects loading="lazy" decoding="async" on all <img> tags
that don't already have loading= set. This tells WebKit to:
- decode images off the main/compositor thread (decoding=async)
- only decode when approaching viewport (loading=lazy)
FIX 2 — CSS max-height:
img { max-height: 600px; object-fit: contain; }
Limits decoded image buffer size. A 1200x900 image still displays
at full width but WebKit doesn't need to composite oversized tiles.
Both fixes are content-rendering optimizations only — no changes
to WKWebView architecture, scrolling model, or layout system.
Also marked Atmos Rewards articles as unread for testing.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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