Toggle display mirroring

Questions & Suggestions
1

I want to be able to toggle display mirroring on and off. I did a search here and saw a reference to a command line tool to do this but when I run this tool (command or it's corresponding app) it is only able to turn mirroring off. It won't turn mirroring back on. I suppose a change in Catalina has broken the tool (last update looks to be 2 years ago). I ran the code in Xcode and took a look but not being a macOS programmer it isn't clear what has changed that breaks the check for the current state of mirroring. Apparently Command-F1 used to toggle mirroring as well but on my system it doesn't work and in the Keyboard Shortcuts preferences there is no listing for mirroring. Anyway since I haven't found another solution...

I know how to open the Display preferences panel but I don't know of a reliable way to switch to the Arrangements tab and to toggle the checkbox using KM. Has anyone created something like this? TIA!

2

You might run the free Mirror Displays in an Execute Shell Script action.

3

That is the one I tried. On my MBP running Catalina it can disable mirroring but it won't toggle back to mirrored. Does it work for you?

4

On the App Store I found one called "Display Menu" that has menu options which can control mirroring in its free version. I tried it out and it does work. I should be able to use KM to control that app but I need to look into the details as it is a menu bar only app. There is also a Pro version of that app which supports AppleScript.

It turns out the Pro version is only US$1.99 so I purchased it so I can control mirroring and the resolution using an Apple Script triggered by KM. Seems to work fine.

5

Bravo!