Only for advanced rehab or when training
Mini squats and partial squats are preferable to full squats, because full squats may stress the meniscus. Full squats, even if supported, are inappropriate for normal knee rehabilitation. The 'form' of a full squat is very important, with the feet a small distance apart and the knees must not go in front of the toes.
How to squat? Effects of various stance widths, foot placement angles and level of experience on knee, hip and trunk motion and loading Lorenzetti S, Ostermann M, Zeidler F, Zimmer P, Jentsch L, List, R, Taylor WR and SchellenbergF. BMC Sports Sci Med Rehabil. 2018; 10: 14.