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Apple says a bug caused Consumer Reports’ MacBook Pro battery life issues

Apple says a bug caused Consumer Reports’ MacBook Pro battery life issues

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MacBook Pro with Touch Bar
James Bareham

Apple announced today that, after working with Consumer Reports, the company has identified a bug in Safari that caused CR to have inconsistent battery life when testing the new MacBook Pros. The news comes after Consumer Reports made waves around the internet several weeks ago when it chose not to recommend Apple’s new laptops after experiencing wildly variable battery life on the updated models, making them the first MacBook computers to not receive a Consumer Reports recommendation.

Apple is still standing by its advertised battery claims and said that the low battery results were due to a software bug in Safari’s developer mode that specifically affected Consumer Reports’ test methodology. The test apparently “uses a hidden Safari setting for developing web sites which turns off the browser cache,” which Apple claims most consumers would never use (and therefore, never encounter the battery life affecting bug). Additionally, Apple said that once it had identified the issue, “We asked Consumer Reports to run the same test using normal user settings,” and “they told us their MacBook Pro systems consistently delivered the expected battery life.” Apple is also issuing a software update to Safari to fix the bug.

Meanwhile, Consumer Reports says that it will be re-running its battery life test with the software update in place and update its recommendation upon completion. Consumer Reports notes that it disabled caching in Safari for consistent testing across platforms.

However, even if Apple’s update does solve Consumer Reports’ battery life issues, there are still unanswered questions regarding battery life on the new MacBook Pros. Despite Apple’s claims that its own data hasn’t shown any problems, numerous users and reviewersincluding The Verge — have experienced variable battery life on the new laptops that the developer mode cache issue doesn’t seem to explain.


MacBook Pro with Touch Bar review