* You can now undo the deletion of a button or field.
* The maximum number of stacks in use, formerly 10, is now 16.
* The New Stack and Resize Card popup menus now have a PowerBook (640x400)
setting.
* The maximum number of open windows is limited only by memory.
* There is now balloon help for all built-in menus, windows, and many dialog
boxes.
* You can drag many modal dialog boxes (including the object Info dialog
boxes) to where you want them on the screen. If you're running System 7,
you now have access to the Edit menu while a modal dialog box is on the
screen.
* Four new visual effects are now available: push left, push right,
push up, and push down. These visuals are like the wipe set of effects,
except that the push effects appear to push the current card off the
screen.
This article was adapted from the HyperCard 2.2 New Features stack.