Screen develops lines when moved or opened from sleep
I suspected the video data line or loose connection. I did not want to operate without a new one, so I ordered one from iFixit.
Went well and the screen works like it should. (This is my wife's MBPro, so it better work! ;-)
I use a 12 inch strip of duct tape with the sticky face up and the two ends turned down to stick to the table. I place screws in order at the back of the tape and move forward as I take screws out. Been doing this for years and I haven't lost a screw, had one left or gotten one mixed up.