Empty dropdown box when trying to move subtask and changing Issue Type

Hi Atlassian-developers,

when I try to move an subtask into another project, the first step is to choose whether to change the issue type or change parent.

I choose "change issue type" and then there is an empty dropdown-box. I think the empty dropdown is there because I have only one issue type for subtasks. So no other one can be choosen to change. In projects where I have other sub-task issue types the problem doesn't exist.

It's an reproducable bug.

Possible Solution:
There should be a query in the code whether there is another issue type left that the subtask can be changed to. If there is no one a message should pop-up or the option "change issue type" should not be available.

Cheers,
Irene