saving buffer with text properties

[Drew Adams]

Is there any plan to enable users to save text with all of its properties?

The Emacs manual says that `invisible' and `intangible' are not saved. It
would be useful to be able to save a file and, upon reopening, restore all
of the Emacs text properties, including properties that are not predefined.

For instance, I have a library that implements conditional text, as in a
desktop publishing system such as Framemaker: easily hide/show arbitrary
sets of faces in regions etc. However, upon saving, all of this info is
lost.