By downloading Skype Preview, you’ll gain early access to our newest — and coolest — features. Of course, while you’re having fun, know that this is a work in progress, so we’ll be hoping to get your vital feedback as we add new enhancements and features. Simply click the heart icon on the main screen and you will be able to send your comments to our team, helping us shape the future of Skype.
From version Skype Preview 8.33.76.26:
You can always find the latest news on what's happening in the Skype Insider Program in the Microsoft Community forums here: aka.ms/skypeinsiderforum

Thank you for supporting Skype!
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August 16, 2018
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July 31, 2018