An electric window makes dying sounds

[gonzo2227]

I recently noticed that the passenger side window was making a strange noise, so I touched it and saw that it let me push it in a bit.
I took the door apart to see if there was a problem that I could see, and I didn't see anything distinct, except for some white plastic pieces, the color of the mounts. It seems related but I can't figure out why it would cause the motor to move freely after it moves down.
My question is, is this something that can be disassembled and repaired?
And if not, does this seem to be a problem with the electric motor, or a problem with the system of the sliders and mounts?

Many thanks to the helpers.

Berlingo M 2008 1.6hdi