If the only template is removed, the dialog is almost entirely blank. It should reset back to the 'New template' form, or do something with all that white space.

Steps to reproduce:

1. Open Transclusion dialog
2. Add 'cite web'
3. Remove 'cite web'

Result:
Stare at the whiteness

Expected results:
Something, anything, except a sea of white

Version: unspecified
Severity: normal