I have this black outlined box with cursor stuck in it after upgrading from Snow Leopard to Mavericks -- any help??? I can't get rid of it.
Disable any assistive device or app, if enabled/\.
From another thread.
Go to accesibility/zoom/more options/show rectangle... and uncheck that.
Strange outline rectangle on my screen...
That you!! That did it. You guys know your stuff!!
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