The new Version 0.8.4 doesn't randomize the starting points. 0.8.3 is ok.

Has anybody encountered this "bug" too?

I've seen a couple of issues raised where command line parameters' actions were inverted. I wonder if this is one of them. Try un-checking the box. If that fixes it then you should raise an issue in the github project.

---

Using ABSPrusa Mendel Zaphod with Pronterface and slic3r 1.3.0. Printing well with 3mm PLA and ABS through 2 x J Head Mk IV b and Wade Geared Exruders. Controlled using RAMPS1.4 board running Marlin_v1.1.9

No, it doesn't change. I'll report this "bug" in the github project.