Cannot delete folders

[hailwood]

Looks like we have a serialization issue with the javascript as it's sending across [object Object] instead of a list of ID's which seems to come from the below screenshot:

[jonom]

For me, as long as there is a Delete button I can delete a folder fine. But the Delete option seems to randomly decide whether or not it will be visible. All the folders and files in a window will either have the delete option or won't have it, but can't work out what the trigger is for this bug.