WPT details: Existing WPT tests will be used as is. Some additional tests will be implemented and existing web_tests will be moved to WPT.
Enable the CSS image-orientation feature, currently hidden behind a flag. Change the default value to from-image, and apply the property to all images, both content and style. In practice this means that the exif orientation, when present in an image, will be used to orient the image unless the "image-orientation: none" CSS property is present.
The CSS WG recently decided on the new behavior for image-orientation. The default should be "from-image" with "none" as an alternative. https://github.com/w3c/csswg-drafts/issues/4164 Safari has shipped the feature with "from-image" the only value. That is, in Safari the Exif orientation is always used.
Explainers: https://docs.google.com/document/d/1j1UFC9zEzBpZ7BqxHhqBOTZxwfaTFLM0OqgIBoKt0rY/edit?usp=sharing