Environment is Windows XP Professional. Opened Firefox (3.6.8) and an icon displays on the task-bar, but no window. Rt click on icon and options are "Maximize" or "Restore". Clicking on either produces a full locked window. Cannot re-size or drag by top bar. Clicking on the "Maximize" icon in the upper right corner of the window and the window disappears. Window may be reopened by a Rt click on the task-bar icon and selecting "Maximize" or "Restore" Opened another session of Firefox at the same time, and a small window (as small as it can be) appears in lower left corner. Can be re-sized, "maximized" and "un-maximized" and appears to be normal.