Go to the Views control panel. Use popup menu for font size to change the size from its current setting (probably 9 point for Geneva) to another size (10 point). Now click on the desktop background. Now reverse the procedure, going back to 9 point. Click on the desktop again. Do this a couple of more times if needed. Eventually, you will get a system freeze that requires restarting the Mac to fix. At least that's what happened to Ric Camp when he tried this on avariety of different Mac models. I also confirmed it on my 7500.
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