Trigger hook on image replacement

[cssjoe]

Is your feature request related to a problem? Please describe.
Some plugins rely on the "add_attachment" action/hook when an image is added. For example, when an image optimization plugin needs to take action on a new image upload.

Describe the solution you'd like
Call the following code when replacing a watermarked image with a purchased one:

do_action( 'add_attachment', $post_ID );

The $post_ID is the attachment/post ID number.

[nicolepaschen]

I have auto convert enabled. I went into a page and changed an image to one I found using BG Connect Search. When I look in the media library it says it’s converted but the jpeg still goes out when I look at the Network tab of dev tools.

I also tried finding the image and converting it first, then adding it to a page. I still don’t see it served in webp.

I used Unsplash and Flickr images.