The stable build of Chrome is currently on version 51; version 53 should reach users in early September.
Google also contended that its tests -- which measure CPU and GPU power consumption -- showed that all browsers, including Edge and Chrome, depleted the battery at similar rates on Windows 10.
Mozilla did not immediately reply to a request for comment on Microsoft's original claims.
Opera is in fifth place among the top five browsers in all analytics tracking of user estimates and actual usage. Net Applications, for instance, said Opera accounted for 1.7% of all browsers used during May. Chrome, meanwhile, was in the top spot with a 45.6% usage share. Net Applications pegged Edge's share at 5% of all browsers on all desktop platforms, or 28.5% of those on Windows 10.
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