Hitting enter wrongly lead to preview when using Object Editor

Reproduction steps:

• Open the object editor
• Click on the suggester to select a class
• Type "User", select "XWikiUsers" using arrows on the keyboard and type Enter to select it
• Type Enter again

Expected result:

• the "XWikiUser" object is created and the form to fill the values is displayed

Obtained result:

• the Preview page is displayed showing if the page doesn't exist yet:
  
• Clicking "back to edit" leads to the following empty editor:
  

Note that even if it's a usability issue it seems it cannot lead easily to loss of data since if there's unsaved data the dialog asking confirmation for leaving the page is displaying when hitting enter.