I was originally posting this in Hacks, but as it seems this could be an unintentional regression, I'm posting here (feel free to move it if I'm wrong).
I've written a plugin that optimizes images when they are uploaded. However, if a user edits an image after uploading it, the new image does not get optimized. I discovered an 'edit_attachment' action hook that almost works, but if the user clicks Save, but not Update, then the hook doesn't fire.
However, it seems to have disappeared in 3.5 with the new WP_Image_Editor class.
Is this the hook I'm looking for? If so, can it be added back in? If not, is there another usable hook?