Yahoo Mail's web interface is failing to display embedded images in numerous newsletters and promotional emails.
The issue occurs in Safari and Chrome on macOS, as well as Safari on an iPhone. Clicking "Load blocked images" does not resolve it.
The same emails display their images correctly in Apple's native Mail app.
Chrome Developer Tools shows failed image requests to ecp.yusercontent.com, including HTTP 404 responses with content-type: text/html and server: ATS.
The problem persists across different internet connections, browsers, and devices. Please investigate whether Yahoo Mail's image proxy or webmail image-loading functionality is failing.