See #790. Time for new designs!

The idea here is that this is a more artistic "special edition" shirt, which we will rotate out and come up with new designs for in the future. The others should be pretty basic and "evergreen"; this is the place to be creative. Could tie into current or upcoming wallpaper themes, or other topical inspiration. (For example, in 2023, we might have a 20th-anniversary shirt.)

But really, I'll leave it up to the design team to figure out what to do and how to decide!
Red Hat's merch vendor for the Cool Stuff store is http://shop.planetlogoinc.com, and we should find an option from there. We should offer both fitted and straight-cut versions.

Note that since the logo is involved, this issue needs input from either Máirín Duffy or Madeline Peck.