Can't place windows next to each other anymore

@stormsaiHello!  I tested this as well and I was able to place those windows next to each other.  If there are no obstructions as @jpkarlsen suggested, maybe also double check the grid where you're placing the windows.  In order for them to sit next to each other, they must be placed within the solid lines.  If they are placed within the dotted lines, there will be space in between.  This is a limitation of the game and is true for any windows or doors that can be placed next to each other.

Notice the arrow below the window is pointing to the solid line.  These windows are between the dotted lines.

Here the windows are placed between the solid lines and the arrow is pointing to a dotted line.