Which model of Macbook Pro is it?

The 24" HP monitor you mentioned should be sufficient for the test, assuming it's 1440P or 1080P or lower. The 3440x1440 resolution on that LG monitor may be enough to cause the issue, but I think it revolves around macOS and it's "HiDPI" screen modes when used with a "Retina" screen - I don't think that monitor would necessarily qualify, though I could be wrong.


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