If a function is inserted with the insert point (vertical line) in front of the expression, then the scoped (underlined) part of the expression is expected to become the first argument of that function.
This, however, does not work for expressions starting with unary plus or minus
Workaround is to put the insert point at the end of that expression, which is visually odd and non-intuitive.
The example is given for the list operator, could equally be any function inserted from the palette.
It seems that unary plus or minus create an invisible placeholder in front of them, which absorbs any inserts regardless of the scope extension.
