Editable inside widget disappears after other widget drag&drop

[Tade0]

Steps to reproduce

1. Open ​http://tests.ckeditor.dev:1030/tests/plugins/widget/manual/block
2. Insert a doublecolumn widget(empty icon).
3. Cut the code snippet widget that's placed lower and paste it into the first editable in the doublecolumn widget.
4. Drag the code snippet widget somewhere - out of the editable, to the other cell - doesn't matter.

Expected result

Widget is moved, everything else remains the same.

Actual result

The editable in which the code snippet widget used to be disappears.

Other details (browser, OS, CKEditor version, installed plugins)

Opera.