I have been having this issue for a while now and cannot find an answer.
Mac Mini Late 2014
macOS High Sierra
2 x Acer ED242QR Monitors
Connection 2 x Thunderbolt to HDMI
Left monitor image is full screen
Right Monitor Image Black Border
Attempts to fix
Changed arrangement - No help
Changed to Scaled - No Help
in Mirror mode - still black border on RH Monitor
Changed cables - No Help
Swapped HDMI in back of monitor - black border swaps to other monitor
Swapped thunderbolt - black border swaps to other monitor
No matter what i do when i have two monitors connected, one of the Thunderbolt ports is pushing out an image with a black border regardless of which i make primary (or left) monitor.
Please if anyone has any helpful suggestions i am all ears because i am tearing my hair out with this.
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