By default Photoshop use grey for the workspace background color. You can change that by.

默认情况下，Photoshop的工作区背景颜色是灰色的。

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This is normal, because some operations need the background tasks to complete before they can proceed, such as getting the Workspace in sync with work you've done.

这是正常的，因为有些操作在可以继续进行之前需要后台任务先完成，例如使Workspace与您已经完成的工作同步。

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You can also drag the required image into the workspace of the program (just the background image).

你也可以拖动所需的图像到程序的工作区(只能是背景图像)。

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