I guess it's better late than never, but Microsoft has finally managed to fix a high CPU usage bug from five years ago in Mozilla Firefox.
The bug, which is related to the Windows Defender Antimalware Service executable process, is known to cause high CPU usage when running Firefox compared to Google Chrome and Microsoft Edge. Fortunately, the issue finally seems to be resolved.
"According to Microsoft, this will be rolled out to all users as part of regular definition updates, which are packaged independently of OS updates," Yannis Juglaret, a Mozilla developer, wrote on Mozilla's Bugzilla forum last month. (opens in a new tab). "This even includes Windows 7 and 8.1 users, although those platforms shouldn't have had the performance issue with Firefox in the first place, since the ETW events that cause it don't exist on those older versions of Windows. So I can tell, only users who would explicitly disallow definition updates (which doesn't seem like a reasonable thing to do with their AV) would not get the fix."
This update has already been rolled out (opens in a new tab), so expect Firefox users to see noticeably better performance.
Ok so why did it take so long to fix it?
Five years is a long time to correct a mistake.
And while it might be tempting to get conniving and assume that not fixing a Mozilla Firefox bug is Microsoft's way of trying to get users to switch to Microsoft's Edge web browser, there's probably a lot more to do with the fact that the problem is so limited in scope.
Firefox is a great web browser, but it's not the most popular. According to StatCounter's global browser market share data, Firefox is used by just 2,93% of all users, while Chrome and Edge, which are built on the same Chromium foundation, account for just under 70%. of the web browser market (with Edge making just 4,64% of that total).
So in reality, Microsoft probably felt it had a number of better things to do with its developer time than hunt down a niche performance bug that affected so few users. And, according to Neowin (opens in a new tab), Mozilla's own developers appear to have been integral in fixing the bug, so it's likely Mozilla had to do most, if not all, of the work. heavy here.