Shelly1 PM Wiring is weird

I just bought a new Shelly1 PM. Have’t wire it yet becouse i have heard that if you wire it backwards it might explode.

I opened it up just to check things up and what i found is rather peculiar.

The Two L lines (L and L1) that suppose to take the mains voltage line are directly connected to the ground of the device and hence to the cathode of a 16v capacitor.

Now i am just a beginner with electronics but wouldn’t that blow this thing up? I have also heard that some devises depending on the model have the wiring backwards in Shelly1? Bad is that relevant to the Shelly1PM as well?
Should i really directly connect the Line wires L and L1 as it says on the label despite it being used as ground and being connected to the negative of a capacitor?

This is really confusing to me since i am a beginner and i am not sure if this is supposed to be like that or not.

Thank you.

Shelly1PM doesn’t have an external ground connection, and is in a plastic box. It’s not uncommon for devices like that to reference internal DC supply rails to one or other mains wire.