Great looking spool holder from Kres on Thingiverse:

After changing UM to direct drive, new spool holder is required to reduce the stress on the head. This spool holder can be placed on any side of the UM + (and other Ultimaker printers with same wall width). It is simply snapped into place and can be simply removed, but provides enough support for any type of filament. Two corks are needed and they are pushed into the tube on each end as far as possible (for few mm to remain). The tube with corks snaps into the left and right leg and then the whole thing snaps on the UM. When changing filament, remove one of the legs, swap the spool and snap the leg back on.