About the paragraph:
During the removal procedure, make sure to insert your opening picks in the right position to avoid separating the screen from its safety frame.
It was not clear to me what the safety frame was until I opened the phone; I was careful but while opening the phone I slid a pick between the screen and the frame, and they became separated in one corner, I wonder if this resulted to my screen being damaged after the repair.
An image that shows what the security frame is would be helpful.