Improve the global behaviour of edit actions
Current situation
If one edits a property in the property tab, the applied change cannot
be undone when the focus is on the property tab (not the text edit
field(!!!)). The modification can however be undone if the graphical
editor is selected.
This is a glitch in the user experience.
How to reproduce
1. Open an arbitrary example model and a model inside it.
2. Select a model element.
3. Edit a property of the model element (Property view in the bottom)
and hit “enter”.
4. Click anywhere in the background of the propery tab.
5. Observe that neither “Ctrl+Z” reverts the change, nor that the menu
entry “Edit ->Undo” is active.
(from redmine: issue id 2782, created on 2016-12-08, closed on 2017-01-30)