"On a PowerBook 2400 or 3400 running Mac OS 8.0, you may encounter a cosmetic anomaly with Microsoft Word 6.x. When a document is open in Word, any window that "floats" over the white space of the document will get redrawn when you press the Return key. The Control Strip and Word's tool palettes will cause this behavior if they are over the white space of the document.
The easiest way to keep this from happening is to keep the Control Strip and floating windows off the white space of the document window. Alternatively, you can switch to the "Page Layout" mode from the View menu in Word. Apple plans to have this anomaly fixed in the next release of its system software, which is due to be released in December of 1997."