"This preview will include primary browser UI for navigation and tabs, and will be delivered as a combined classic + Metro browser," said Bondy. "I believe there is a Q4 goal for a beta release as well."
Windows 8, which is available now to some Microsoft customers, hits retail on Oct. 26.
Mozilla was the first Microsoft rival to announce it would create a combination desktop and Metro-style browser to compete with Internet Explorer 10 (IE10) on Windows 8.
Google later joined the race, and in June beat Mozilla to the preview punch by releasing an in-progress browser that runs in the Metro user interface (UI).
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