The links in categories Links and Blogroll will now go to a new Tab.
This was done by clicking Links and then Edit in the Dashboard at the left. Select the link to change and click edit, click on the new target (_blank for example), then finish with Update Link.
The editor also allows you to delete links (which we thought must be the case, of course).
The only remaining puzzle with Add New Post is the mysterious “Path: p”, below. Please explain.