Update CHANGES.

CHANGES

@@ -1,6 +1,55 @@
 CHANGES FROM 2.8 to master
 
-* ...
+* Add -Z to find-window.
+
+* Support for windows larger than the client. This adds two new
+  options, window-size and default-size, and a new command,
+  resize-window. The force-width and force-height options and the
+  session_width and session_height formats have been removed.
+
+  The new window-size option tells tmux how to work out the size of
+  windows: largest means it picks the size of the largest session,
+  smallest the smallest session (similar to the old behaviour) and
+  manual means that it does not automatically resize
+  windows. aggressive-resize modifies the choice of session for
+  largest and smallest as it did before.
+
+  If a window is in a session attached to a client that is too small,
+  only part of the window is shown. tmux attempts to keep the cursor
+  visible, so the part of the window displayed is changed as the
+  cursor moves (with a small delay, to try and avoid excess redrawing
+  when applications redraw status lines or similar that are not
+  currently visible).
+
+  Drawing windows which are larger than the client is not as efficient
+  as those which fit, particularly when the cursor moves, so it is
+  recommended to avoid using this on slow machines or networks (set
+  window-size to smallest or manual).
+
+  The resize-window command can be used to resize a window
+  manually. If it is used, the window-size option is automatically set
+  to manual for the window (undo this with "setw -u
+  window-size"). resize-window works in a similar way to resize-pane
+  (-U -D -L -R -x -y flags) but also has -a and -A flags. -a sets the
+  window to the size of the smallest client (what it would be if
+  window-size was smallest) and -A the largest.
+
+  For the same behaviour as force-width or force-height, use
+  resize-window -x or -y.
+
+  If the global window-size option is set to manual, the default-size
+  option is used for new windows. If -x or -y is used with
+  new-session, that sets the default-size option for the new session.
+
+  The maximum size of a window is 10000x10000. But expect applications
+  to complain and higher memory use if making a window that big. The
+  minimum size is the size required for the current layout including
+  borders.
+
+  This change allows some code improvements, most notably that since
+  windows can now never be cropped, that code can be removed from the
+  layout code, and since panes can now never be outside the size of
+  the window, window_pane_visible can be removed.
 
 CHANGES FROM 2.7 to 2.8