I printed in PLA 0.3 draft layer height with brims.
I had to clean up magnet holes a bit before magnets fit snugly in. There was a bit of a gap between front and back so I used a soldering iron to further sink the magnets in place. One magnet would not stay in place so I used a bit of super glue.
For more info look at original by shakeNbake08 at https://www.printables.com/model/213059-logitech-mx-master-3-case
The author remixed this model.
Changed magnet holdes for 8mm dia X 3mm magnets.