If you place 4 chests in a row (or create 2 double chests any way where they are right next to each other) and it will be allowed. In earlier versions single chests could not be placed right next to each other, and in MC PC that behavior is not allowed
MCPE-4875
Double chests can be placed directly to the side of another
Resolved
Duplicate
0
Is there any buggy behavior with it, such as shared inventories across chests? If not, it's more than likely a feature.