Instagram is turning the tables on its iconic square grid layout. The social media giant is currently experimenting with a bold new look for user profiles: vertical rectangles instead of squares.

This potential facelift comes as Instagram adapts to changing user habits. According to Adam Mosseri, the platform’s CEO, the vast majority of content uploaded these days is vertical. Whether it’s 4:3 photos or 9:16 videos, most posts are taller than they are wide.

The current square format, Mosseri admits, is a holdover from Instagram’s early days, when only square photos were allowed. That restriction was lifted in 2015, but the profile grid has remained stubbornly square—until now.

While the change may freshen up the look of the app, not everyone is jumping for joy. Many users have spent countless hours perfecting their profile grids, carefully arranging square posts to create eye-catching patterns or tell visual stories. The shift to vertical rectangles could throw a spanner in the works for these carefully crafted layouts.