CWmike writes to mention that the "Windows Presentation Foundation" plugin that Microsoft slipped into Firefox last February apparently left the popular browser open to attack. This was among the many things recently addressed in the massive Tuesday patch. "What was particularly galling to users was that once installed, the .NET add-on was virtually impossible to remove from Firefox. The usual 'Disable' and 'Uninstall' buttons in Firefox's add-on list were grayed out on all versions of Windows except Windows 7, leaving most users no alternative other than to root through the Windows registry, a potentially dangerous chore, since a misstep could cripple the PC. Several sites posted complicated directions on how to scrub the .NET add-on from Firefox, including Annoyances.org."