Steps to reproduce:
1.Open a page with VE
2.Go to Insert>Reference
3.Type something in the text box
4.Click on "Insert Reference"
5.Again re-open that reference
6.Delete the content inside the text field
issue 1: The "Use an existing reference" button remains enabled when user has entered something in the textbox (step 3), it should be disabled as soon as user enters types something in the field.
issue 2:After clicking on "insert reference" , when user reopens that reference, there is no "Use an existing reference" button in the reference dialog box (step5), the button should appear there but as "Disabled"
Once user deletes the content inside the text field (step 6), the button should again re-anabled.