Dropdown list with value maps is empty in item details screen

Steps to reproduce:

1. Go to Configuration -> Templates
2. Edit a any existing template
3. Click on items tab
4. Edit any existing item
5. Click on dropdown Show value.

Result:
Dropdown list is empty
unable to type in any value
unable to save the item with error field valuemapid is not integer
Expected:
Dropdown list with all value mappings
currently selected value mapping as default value in "show value" field