Currently variable highlighting on mouseover is only enabled in the Program window for the variables defined for variables defined in the topmost level of procedures/function. If the variable is defined in an anonymouse block in the declaration section, there is no highlighting for it. Also if you define a local procedure inside a procedure and put mouse over a variable defined in the parent procedure standing inside the local procedure there is no highlighting also. And no highlighint for SQL window at also.
Please enchance the highlighting feature for the listed cases.