- non-attached annotation => suggest a derived filename for save-as
- lasso selection tool
- prefs file, save prefs
- recent files list

- flatten (incl undo/redo...) - enabled only if nlayers>1
- bg: apply to all pages
- recolor selection
- resize selection
- move selection to another page by drag-drop
   (should apply to vertspacer when origin moves to another page,
     but in the up direction only do so when all the stuff fits on prev page)

- text tool, font chooser, default font
- color chooser (papercolor, pen color); maybe more default colors
- printing: print-to-PDF? (with & without pdf background to merge)
            opacity issue for highlighter strokes (maybe print them below ?)
            save gnome printer settings (throughout a session, and on disk)
                 (maybe a separate config file .xournal/gnome-print-settings)
....
- file print-options, own print-to-ps/pdf 
- help index
- pressure sensitivity
- insert images (screen capture or from file), not as full-page backgrounds
- more pen/highlighter shapes (chisel)
- convert to/from Jarnal format
- recalibration upon screen resize / compensation for miscalibration