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Has anyone been able to use sidecar normally with the upgraded 3.1 GHz logic board since the early 2015 with the 2.7GHz cannot use sidecar, but the early 2016 with 2.9 GHz can?
This system does not meet Apples requirements for sidecar support macOS 10.15 Catalina Sidecar Compatibility For Mac: Here Are The Details