So, Blizzard is offering a gift to players for some reason (possibly for a bug, I forget). But on my Linux install (via Playonlinux), clicking the Gifts button at the top just brings up a blank screen. You are supposedly also able to claim the gift by logging onto battle.net in a browser. But where does one go from there? There's a "Gift history" option in your account settings section, but that does not list anything that is claimable. So, looking through their help section, the answer apparently is to visit https://account.blizzard.com/gifts where the gift should be ready to be claimed if you visit before Feb 2nd. The page lets you choose which regional account you want the packs credited to.
Regional mirrors of the same page are accessible via: