D12 and TAdvStringGrid error

I get an error using OnGetAlignment

From Delphi Help file
"You are assigning a method to an event property even though they have incompatible parameter lists. Parameter lists are incompatible if the number of types of parameters are not identical. For a list of compatible methods in this form, see the dropdown list on the Object Inspector Events page."

Code works perfectly in D11, unchanged code fails i D12.

The error occoures when doubleclicking in the event OnGetAlignment.

How to solve this?

I tested this here dropping a grid on the form of a new application, implement OnGetAlignment and I do not see any issue.
What are you doing different?

Nothing special really.

I doubleclick in OnGetAlignment to make the event handler in code.

When I make a new test project there are no errors, when I try to double click in my main project there is the above mentioned error.

Please provide sufficient details to allow us to reproduce this.