I usually add images to chapters by downloading them from sites like flickr or Wikimedia Commons and then uploading to the media library. As a test I tried adding through just inserting a URL from flickr, which worked great except that it doesn’t seem to give me the option of adding alternative text or a caption. It’s just the image on the page and it’s not clear where it’s from (though you can click on it and it goes back to the original).
I’m guessing that one can only add alt text and captions to images in the library, because adding by URL is basically like just adding a link…is that correct? I tried doing a couple of web searches to find the answer but couldn’t find anything that talked about this specifically.
Just wanted to double check, because if I can’t add alt text or captions I won’t be adding images by URL!