Instagram: Image, Carousel
The recommended size changed from 4:5 (1080 × 1350) to 3:4 (1080 × 1440).
The Instagram profile grid is 3:4. A 3:4 (1080 × 1440) image fills it exactly, where 4:5 (1080 × 1350) lost about 34 pixels on each side. Every carousel slide follows the first, so the carousel changes too. The safe zone edge is gone, because nothing is cropped in the grid anymore. LinkedIn stays at 4:5 (1080 × 1350).