Perspectives also need to interact with the tabs.
+** FFI (foreign function interface)
+See eg http://lists.gnu.org/archive/html/emacs-devel/2013-10/msg00246.html
+
** Imenu could be extended into a file-structure browsing mechanism
using code like that of customize-groups.
** Highlight rectangles (`mouse-track-rectangle-p' in XEmacs). Already in CUA,
but it's a valuable feature worth making more general.
+ [Basic support added 2013/10:
+ http://lists.gnu.org/archive/html/emacs-devel/2013-10/msg00904.html ]
** Eliminate the storm of warnings concerning char/unsigned char
mismatches that we get with GCC 4.x and proprietary compilers on