Calculations show that between 165 million and 184 million copies of Windows 8 are being used to access the Web.
Microsoft has delivered a stopgap defense for active attacks against Internet Explorer 10, and is not likely to ship a patch before March 11.
All extensions on Windows must be installed from the Chrome Web Store; those that were not will be permanently disabled
Use of the so-called Directory Tiles that include ads will help keep Firefox free of charge and support Mozilla's ongoing projects, the chair of the Mozilla Foundation says.
But extends end-of-sales date for business PCs running Windows 7 Professional
Apple's revenue from music, apps and services equal 91% of what Microsoft made from the group that sells Windows to computer makers.
Microsoft will also end support for Office 2003 and Exchange 2003 as well.
Two more updates boost the total for tomorrow to seven, including patches for Internet Explorer and Windows XP.
This year's contest offers a grand prize of $150,000 that requires researchers to deal with Microsoft's EMET anti-exploit toolkit.
Three of the four updates for Windows on Patch Tuesday will affect Windows XP, which is scheduled for retirement in April.
As the countdown to Windows XP's cutoff continues, the company encourages users to help users to upgrade, but offers no discounts for the new OS.
The soon-to-be-retired Windows XP is gaining user share while adoption of Windows 8 and 8.1 stalls.
After last year's semi-washout, the March security contest will again try to draw out exploits of the Chrome operating system.
Microsoft's financial reports indicate it took a $39 million hit on its tablet sales during 2013's fourth quarter.
Two-thirds of "brand marketing messages" were opened in Q4 on a smartphone or tablet as another task flees the personal computer.