lfRestrictSelectOptions does not show the desired effect

[C Streic]

Good evening,

I have a live field where I want to hide certain options depending on the user. I have 10 different options (A - J) and want to show options A - E for user 1 and E - J for user 2. If one of these two users selects option E, another text field should appear. 

To achieve this I wrote something like:

lfRestrictSelectOptions("field", {"A", "B","C","D"});
if(argv["field"] == "E") {
 lfShow("textfield");
 }
 else {
 lfHide("textfield");
 }

and 

lfWatch("field",allFields, "Hook.sil");

Everything works, except that, if a user makes a selection, the "field" immediately jumps back to NONE. 

If I use

lfWatch("field",allFields, "Hook.sil", {"keyup"});

 I does not jump back to NONE, but the hidden text field does not appear, if a user selects option E.