I have this laptop since 2018 and I have just now first took it apart for cleaning and to install ram/ssd.

In the process, I had to remove a paper/plastic piece near the fan of this lenovo y520 laptop.

As such I must wonder what is the use for this sticky paper/plastic piece?

would it be bad if I were not to put it back in where it was from? It's barely even sticky at this point, not sure how I could have got it off without ripping some of the adhesive layer off