Joey has this trick of embedding the Windows logo image within the kbd tags. So
<kbd>![Windows Key][winlogo]</kbd>
Combined with a regular key, looks like:
R
Here's a better one that shows the 4 parts clearly:
R <kbd>![Windows Key][newwinlogo]</kbd>
Although FWIW I like the old one much better:
R <kbd>![Windows Key][oldwinlogo]</kbd>
Here are the images you have to use in your post's source code:
[winlogo]: https://i.sstatic.net/Rfuw7.png
[newwinlogo]: https://i.sstatic.net/B8Zit.png
[oldwinlogo]: https://i.sstatic.net/T0oPO.png
