It's even worse than what you said: the <img> tag has a srcset attribute with many possible values so different people may see different images depending on the

It's even worse than what you said: the <img> tag has a srcset attribute with many possible values so different people may see different images depending on their browser's resolution. The one displayed to me was Shoot-Antoine-0044-_DSC0085-lossless-800x450.webp, which shows clear posterization at its native size as well as when it is further scaled down by the browser to 550x309.