Inconsistent image handling in wp_create_image_subsizes.

[ddur]

New "big image handling" uses $editor->resize() which will not only resize, but also loosely compress JPEG image (degrade image quality) by invoking $editor->thumbnail_image() inside $editor->resize().

Rotating image below "big image handling", about line 322 in image.php uses $editor->maybe_exif_rotate(), which will not further degrade image quality.

Until WP version 5.3, media editor page was always starting with original/upload image quality, which is not case after WP 5.3+ "big image handling" is triggered.

IMHO, media editor page should never get "thumbnalized" image as starting point for further editing by user.