How to save cookies when the app write to document.cookie?

I'd like to understand how to save cookies that the application writes to document.cookie (https://developer.mozilla.org/en-US/docs/Web/API/Document/cookie) , as I've noticed that the common methods wget/curl to save to a file does not work for this particular case, it seems. Assuming the web app writes cookies: document.cookie = name + "=" + value + expires + "; path=/"; For example, wget --keep-session-cookies --save-cookies cookies.txt "http://foobar/app-generates-cookie.html " or the curl, curl --cookie-jar cookie.txt http://foobar/app-generates-cookie.html Both wget/curl does not work for the app case above.