So this is nice but doesn't do what I'm looking for, which is: given an email with links like OP's (https://www.google.com/...), go over it, follow each link to its final redirect and then replace the href with that (in this case, https://www.slashgear.com/...), letting me (for example) preview the links on mouse-over before clicking.
I thought it might be possible to build something like this with curl -Ls -w %{url_effective}, but seems like it only handles HTTP 302 redirects, whereas this site seems to be using Javascript, so you probably need a real crawler.
https://addons.mozilla.org/en-GB/firefox/addon/clearurls/