Reference Error - existing switch-item supposedly not defined

This rule referring to an existing (and in my opinion defined) item …

if (items[SiemensBackofen_PowerState]=="ON") {events.sendCommand("v_schalter_backofen_tur_schon_geoffnet","ON");}   

… leads to this message in frontail log viewer:

2021-04-13 19:32:54.661 [ERROR] [internal.handler.ScriptActionHandler] - Script execution of rule with UID 'Backofen_Tur_geoffnet_setzen' failed: ReferenceError: "SiemensBackofen_PowerState" is not defined in <eval> at line number 1

…although the item does exist:

Does anybody have an explanation for that?

in DSL it is items.SiemensBackofen_PowerState.state - not sure about JS. maybe the same?

No that was not it. But with a fresh look at it, I saw the (in hindsight) obvious: I forgot the “”
It’s got to be:

if (items["SiemensBackofen_PowerState"]=="ON")