In cx2-testing start a translation and right-click on a link (red or blue) in the source article. The Console will display the following error for each click:
Uncaught TypeError: Cannot read property 'ownerDocument' of undefined at Function.Sizzle.contains at Object.OO.ui.contains at VeCeSurface.ve.ce.Surface.showSelectionState at VeCeSurface.ve.ce.Surface.fixupCursorPosition at VeCeSurface.ve.ce.Surface.onDocumentSelectionChange