While the Frick’s old mansion undergoes its first renovation in 85 years (the second floor opens to the public next year), the Frick Madison is serving as a temporary home. The museum took over the Met’s lease on the Breuer building, allowing its permanent collection to remain a staple of the Upper East Side. Though the homey quality of the stone walls will be missed, the austere environment refocuses the masterpieces. Highlights include a chapel-like room for Giovanni Bellini’s St. Francis in the Desert, which lets in light from 75th Street. —E.C.