Hello,
On my portfolio items (on the home), i expect to list (and filter by category if needed) the 9 items of the portfolio. The first row has the three first items. But on the first thumbnail in the second row, i have an empty square (instead of my 4th portfolio). On the ipad, the empty space are 2nd row / 1st column  and 3rd row / 1st & 2nd column. 
Looks like on PC
XXX
 XX
XXX
X
Looks like on the iPad
XXX
 XX
  X
XXX
The 9 items in portfolio are visible by the way.
Where does it come from ? thanks in advance.