- Use Mouse For Touch - No longer working in 18.3

I have a simple Project in 17.3. which heavily uses the “Use Mouse For Touch” property. All is working fine there.
I now updated the project to 18.3 because of the AR features. All the Touch Events (on Input Touch Begin) are no longer working in the editor.

Normal Click Events of my Mouse are working though. Do someone has the same issue or know a solution? Could this be a bug?
Any help would be much appreciated.

Thanks in advance.

I have to excuse myself. Use Mouse for Touch is still working.
BUT
On my MacBook the area which receives the touch is shifted away from the object. But if I use a normal Click Event, it receives the Event on the right area. Strange. This must be a scaling issue. I will post another question concerning this problem.