At the same time, Edge's weakness counters Mozilla's assertion that because Windows 10 adopts the browser as the OS's default -- even if another had been set as the default on Windows 7 or 8.1 prior to upgrading to 10 -- Microsoft is unfairly leveraging its dominance in the desktop operating system market.
In a letter last month to Microsoft CEO Satya Nadella, Mozilla's chief executive, Chris Beard, slammed the switch to Edge. "The update experience [of Windows 10] appears to have been designed to throw away the choice your customers have made about the Internet experience they want, and replace it with the Internet experience Microsoft wants them to have," Beard wrote.
Mozilla published the letter to Nadella on its website July 30, a day after Microsoft began distributing Windows 10.
But the data from Net Applications and StatCounter show that the change to Edge promoted through Windows 10's Express Setup process has not resulted in a wholesale replacement of rival browsers.
That's not to say Beard's concerns were unfounded, either for Firefox specifically or non-Microsoft browsers in general. And it's entirely possible that Edge's user or usage share will grow as a percentage of the comparable statistics for Windows 10.
Yet the latest numbers from StatCounter -- which, again, measure activity, not users per se -- aren't encouraging for Microsoft and Edge. Since Aug. 1, Edge's share of Windows 10 has slipped, not snowballed as might be anticipated as the OS's user base accumulated more mainstream users and presumably tilted away from enthusiasts and power users who could be expected to retain their prior browsers.
In the past seven days' of StatCounter data, Edge activity accounted for 15.4% of Windows 10 activity overall, down from 16.6% during the seven days before that.
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