Can I downgrade macOS 13 Ventura to macOS 10.14 Mojave on my Mac mini?

You may be able to run macOS 10.14 Mojave and still keep macOS 13 Ventura on the same computer

Then, you can Test if the Display Issue only appears in Ventura or Not

If you entertain this idea, the computer would become a Dual Boot Setup

To read up more on this ability, follow the link below

Suggest reading All the Article before moving forwards with this

If it not for you - leave it alone

Use more than one version of macOS on Mac

Becky244 wrote:

I'd be very very happy to change from ' Ventura' to. OS 10.14

FWIW, that would be a very bad idea. It would be much better to sort out whatever problem you are having with the monitor.

OP wrote " I've read the 2018 Minis have issues with the combo of the New OS 12 / 13 and displays - and apple has not fixed. ??? "

Having used a M1 Mac Mini that came with macOS 11 Bug Sur and since upgraded through every newer version of macOS up to an including macOS 15.1.1 Sequoia ( before retiring it for M4 Mac Mini )

The only Semi Display issue was fixed by getting a new Cable from computer to Display

So the premise that there is, an Implied Unfixed Bug is macOS 13 Ventura that has not been fixed

Well seems a bit misguided

Ventura has received 30 Updates since it was First Released culminating in current Ventura 13.7.2.

The display issue seems localized to this computer or / and how the Display is connected to the computer