I've found this is conflicting with the inline moderation tools.
Usually when you click the checkbox on a post it highlights it (makes it yellow) then you scroll down to the bottom of the page and the dropdown menu shows you how many posts you've selected, and you can move/delete/merge/etc.
With these buttons added the posts don't get highlighted and it says 0 in the dropdown menu, even if some checkboxes are selected.
I will keep testing and hopefully find a fix but thought I'd post here in case anyone had any suggestions?
Thanks!