Emails with multipart/related structure reference embedded images via cid: URIs. The WebView's CSP only allows data:/blob: sources, so those images were never shown. injectInlineImages() now replaces each cid: reference with a data: URI using the decoded bytes from the MIME tree, both for double-quoted and single-quoted src attributes. Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>