hi Liza5, maybe that's an issue with hardware acceleration - please try updating your graphics driver or in case there is no new version available at the moment or this doesn't solve the issue, disable hardware acceleration in the firefox menu ≡ > options > advanced > general (that setting will take a restart of the browser to take effect).

Thanks, Philipp. Your reply made me feel as though someone was hearing me, and that was a good thing. My husband and I went through the steps you gave us and the problem was still there. We sent the new display (monitor) back to the company and they have sent us a new one. This new one does not have the problem, happy to say.

We appreciate your help. Thank you!

Hello,

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