Microsoft Office insider preview build 15.23 for Mac is now available for testers. Insider team posted the information on twitter.

Office 2016 Insider Build 15.23 features

Export to video: In PowerPoint, click File > Export and then select MOV or MP4 to export your presentation as a video that can be burned to a disc, uploaded to the web, or sent in an email message.
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Full customization of the Ribbon and Quick Access Toolbar: In Word, Excel, and PowerPoint, you can now customize the Ribbon and the Quick Access Toolbar to suit your needs.Office_Mac (2)

Export to ODF: In Word, Excel, and PowerPoint, you can now export files to OpenDocument Text (.odt), OpenDocument Spreadsheet (.ods), or OpenDocument Presentation (.odp) format.Office-2016-mac

Class Notebook Tools:  You can now distribute pages and sections to students, quickly review their work, and more easily access the Class Notebook app.

Check Office update in Mac, a new build 15.23 is now available for download if you are a Mac Office insider. Microsoft added Thai and Czech language support to Office Insider on Mac.

Update: Microsoft added Thai and Czech language support to Office Insider on Mac.

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