When i type the line (using code-completion):

System.getProperty(

a blue-highlighted dummy argument appears after the ( and is replaced when i
type, but what i type is still highlighted blue until i hit ENTER (or space?)

But if the argument that i type in is infact another method call also chosen
through code-completion, the blue highlighting does not "step into" the inner
method's argument. That is, i would expect that the inner method call's argument
would then be highlighted blue. When i had finished entering that argument, then
the blue highlighting would return to the original argument, before the final
ENTER would remove all the blue highlighting leaving you at the end of the
statement's line.