Only the foreground window can capture the mouse.

只有前台窗口可以捕获鼠标。

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An active window is the foreground window in which the user is working.

使用中视窗是使用者在其中作业的前景视窗。

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Also, even if the foreground window has captured the mouse, the user can still click another window, bringing it to the foreground.

另外，即使前台窗口已捕获鼠标，用户仍可以单击另一个窗口，从而使后者成为前台窗口。

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For example, a floating windows user could monitor a stock ticker in a background window while working on a report in the foreground.

FORBES: Look, Ma, no glasses!