'Move left' and 'Move right' buttons broken for labels in Edit drop-down menu

[thepurpleblob]

To reproduce..

• create a label
• on the course screen, select the 'Edit' drop down down menu to the right
• Clicking 'Move left' or 'Move right' does nothing

[thepurpleblob]

Ahh... it is indeed the same as the previously reported one. I just can't type :(