For consistency, on desktop, the navigation arrows are back below the move log. On mobile they are locked to the bottom of the screen.
This results in a larger board for game analysis on desktop.
If you want a larger board still, any board with the spare pieces below it* now also has an additional 'expand board' option - top right, below the 'invert board' and 'board options' icons, which will remove the spare pieces and expand the board in its place. This is not a persistent choice, but if you want a bigger board with less noise on the page, you can toggle this on and off at will.
*For dragging on to the board, available on the analysis board, FEN viewer, and some others such as puzzle creation. I refer to it as the piece bin.