I have Mac mini with macOS Mojave 10.14.6 and a new HP 23" Monitor. HP does not have driver for my OS and says to get from Apple

Displays should not need drivers.

I have hooked up a wide variety of displays to an equal variety

of Macs and have never needed any sort of driver.

If you tell us what year model Mac Mini you have?

see > Identify your Mac mini model - Apple Support

Plus exactly which model HP Display you have?

see > https://support.hp.com/us-en/document/c00794706

Then perhaps we can help you choose the proper cable or adapter and cable that you need to use.

I have a mac mini (Late 2014) with a Samsung C32F391 monitor that was working until I updated to mac OS Catalina and now the display is larger than the Samsung monitor screen. When I look at the Display settings the resolution is "Default for Display" is checked, other option is "Scaled" with 3 sub options 1. 1600x900 (still too large), 2. 1080p (still too large) and 720p (large icons and top tool bar menu is barely visible). connection is through HDMI cable.

I have a similar problem. I was running an iMac [21.5 inch, late 2015] in a dual monitor configuration with an LG 24MP56HQ. Connection is through an HDMI cable to the Thunderbolt port. This worked great until I upgraded to Catalina.

All of the LG drivers for the monitor are Windows compatible with no Mac equivalent. LG tech support is not responsive. Is anyone aware of a generic Mac driver that will work with this monitor?