Where does this little rubber part go?

[thinairflyer]

I removed the rear cover to replace the switch strip and a little rubber part fell out.  I can't figure where it goes and searches have not given me an answer.  It is about 3/16" x 1/8" rectangular in a little box configuration with a small hole in the bottom if the box.

I have an image but am unable to attach it, I get the error message that the upload folder is full.  The images in 16kb in size.

[thinairflyer]

I have looked at dozens of images of the tablet and have not seen the part in any of them.

The part is not at all deformed as it would be if in a position of being compressed between the back and the circuits of the tablet.  It freely fell out when I removed the back.

I have been an electronic tech all my life (I'm 80 years old now and retired when I was 78) over a very broad range of equipment and devices, so feel if there was a place for the little rubber part I would normally find it.  Apparently, as no one has posted to note where it goes, I am beginning to wonder if it is placed inside the back of the tablet to be removed and discarded to indicate that the tablet has been opened; much like the little piece of plastic that in years past (may still be, I don't know) was placed in the pan of automatic transmissions to indicate to a dealer's repair section that the pan had been removed and the part was tossed by the remover when he could not find a place for it. Or maybe it was inadvertently placed inside the tablet by someone who opened the tablet at some time.

Or maybe it was placed inside by someone to make someone (me in this case) scratch their head trying to find a proper place for it.  LOL!