How come my LG monitor won't work in Mojave like it did before the upgrade?

Hi maggySwim,

Thanks for using Apple Support Communities. It sounds like you’re having trouble with your external display after updating your Mac. We’re happy to help.

We suggest trying the steps outlined in this article: If your external display isn't detected or appears blurry on your Mac - Apple Support

Should the issue persist, please let us know more about what is not working with your monitor after updating.

Take care.

maggySwim,

Thanks for getting back to us. Can you let us know what happens when you try to use your display now? Is it not detected by your Mac or something else? What is the exact version of your Mac? Check by clicking  > About this Mac (Upper left corner). What is the model of the LG monitor?

We look forward to your response.

Thanks for the additional information, maggySwim.

Next, we suggest contacting LG to see if there are any firmware or driver updates for your display: Get Product Help & Support | LG USA Support

If that doesn’t help, contact Apple Support.

Best.