--- a/eric6/ViewManager/ViewManager.py Fri Nov 01 16:11:55 2019 +0100 +++ b/eric6/ViewManager/ViewManager.py Sun Dec 01 16:38:47 2019 +0100 @@ -5436,9 +5436,15 @@ """ Public method to handle the global change of focus. - @param old reference to the widget loosing focus (QWidget) - @param now reference to the widget gaining focus (QWidget) - """ + @param old reference to the widget loosing focus + @type QWidget + @param now reference to the widget gaining focus + @type QWidget + """ + # Focus handling was changed with Qt 5.13.1; this copes with that + if now is None: + return + from QScintilla.Shell import Shell if not isinstance(now, (Editor, Shell)):