MAS 36 Saftey Question

I picked up a used and abused MAS 36 recently, very inexpensively. As I explain you'll understand why. Bubba got to it and "sporterized" it. But I figure I can put it back together and have it look 95% like a milsurp MAS 36 just with an enfield muzzle as Bubba chopped the barrel a few inches! So the muzzel crown will just stick outside the fore stock when finished...I think.

Anyways I just got it and haven't even had time to clean it up, I have but 1 question. What is that thing rattling around just under the back of the bolt? It appears to function like a saftey...when pushed in (toward the bolt) the trigger will not fire, when pulled back the trigger can fire. The problem is I understood the MAS 36 had no saftey!? And even worse if I hold the gun aimed toward the ground the saftey engages by gravity and yup you guessed it if I aim it skyward it disengages!

It is the turned up lip to the right of the end of the bolt in the picture.

Is this a saftey? Is this something someone added on importation? Can I remove it, tighten it up, do something with it so it doesn't rattle around and randomly put the rifle in and out of safe mode??? I have fallen in love with the looks of this rifle and I wanted a project to play with so I really want to make this thing work!

Thanks in advance for any guidance.