The latest software updates, version 22.214.171.124 for the Fire TV and version 126.96.36.199 for the Fire TV Stick, are currently making their way out to all Fire TV devices. If you haven’t received the update yet, be patient as you’ll receive it eventually. I’ve had a chance to compare these new updates with the previous version on both the Fire TV and Fire TV Stick and have been unable to find any visible changes to either device.
Amazon has just updated their Fire TV and Fire TV Stick software pages to reflect these new updates and have listed “Bug Fixes” as the only change. I was expecting Windows 8.1 Miracast support to be added with this update, but it doesn’t look like that’s the case. The Fire TV Stick product page still lists the feature as “coming soon.” Due to a power surge taking out my Windows PC, I’m unable to verify that Windows 8.1 Miracast support was not added with this update. If you get a chance to test mirroring a Windows 8.1 PC or find any changes with these updates, be sure to let us know in the comments.