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Single red vertical line on iMAC display

Noticed a single red vertical line on my iMAC display after upgrading to Big Sur. Is this a hardware of software issue?

iMac 21.5″ 4K, macOS 11.0

Posted on Dec 6, 2020 5:14 AM

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Posted on Dec 6, 2020 6:14 AM

Try booting into safe mode How to use safe mode on your Mac - Apple Support Does the red line persist?

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Single red vertical line on iMAC display

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