please add safety to node deletions

As others have noted, undesired deletions have been a concern. I see two mitigations that avoid the trouble of re-opening tabs from Chrome. One is to strictly maintain the three-button layout of "comment", "delete", "save/close". Safety is added by keeping the trashcan area and the green X area separated. The second is to require confirmation of a delete command. Three options that come to mind are, having the delete button respond only to a double-click, using a popup, or using a two-state button that requires two consecutive hits to activate.

Another safety feature I've seen in competitors is a "lock" icon, that prevents deletion by any means while in the locked state. I strongly urge the adoption of *some* form of safety mechanism, if you please.