Comment 7 for bug 316922

I would like to give an use-case of this features:

"
Inside the work view mode, you won't see the parent of the tasks. In case that you have two tasks with the same name , or the summary of the task is too brief that you can't remember what it mean. You may need to check its parent for more information. Without the "link to parent" button , user need to close work view mode , and search the task again.
"

For the implementation , I would suggest to add a gtk.MenuToolButton next to the "Insert Tag" button.

1. User press on the popup menu toggle button , it will show all the parents.
2. User press on the button, it will show the first parent encountered.