I tested several Kendo UI versions up to R1 2015 and the exhibited behavior was identical, so something with regard to how js code executes in an anchor's href tag must have changed in the latest versions of Firefox, i.e. it is not a change in the Window introduced by us that is behind this.
The suggested use of void(0) should be applicable to all scenarios when you want to execute some arbitrary code, instead of navigate, on clicking an anchor.
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