🚀 go-pugleaf

Re Henry Thompson's recent posting:

Smalltalk did indeed use backing store for both pop-up menus and
independent windows as early as the late '70s.  However, what I've
gleaned from the discussion here is that the patent is specifically
on Rob Pike's elegant method for saving only the obscured parts of
windows, specifically for the purpose of making updating of partially
or totally obscured windows efficient.  Xerox/ParcPlace Smalltalk
didn't implement writing to obscured windows until the late '80s.

I use the word "gleaned" deliberately: I haven't yet seen anyone who
has actually *read* the patent post a summary of its contents.  Did I
miss something?