Describe the bug

When clicking the + (plus) for adding a translation in the documents list a blank edit form is shown where the new language is selected in the WPML metabox. But the relation to the original post is not created.

In document list the posts are now both listed but without being a related translation. It's still possible to click the "+" again to add another translation for the same language.

Steps to reproduce the behavior

1. Install and configure WPML (Default language: de_DE, Second language: en_GB)
2. Add a document
3. Go to the document list in backend
4. Click to the + in the language column
5. save the translation
6. Go back to the document list
7. Chose "All languages" from the WPML Dropdown in Admin bar
8. See that there are now two unrelated documents

Expected behavior

When translating a document the relation to the document of original language should be saved.

Screenshots