Save/Open stack to/from variable?

[hh]

In a situation where you can't 'directly' access the filesystem
in order to save or read a stack but can write any variable to a
local file and read from any local file to a variable,
the questions arise:

• Can we save (the current state of) a stack to a variable in a
format as the usual stackfile (may be base64 encoded)?

• Can we open (and set the state of) a stack from a variable that
is in usual stackfile format (may be base64 encoded)?

The "read" question describes an extension of "go stack url" where
the url is a variable in usual stackfile format.

And yes: I don't mean script only stacks.

For example in a HTML5 standalone we have such a situation.
May be also in some mobile standalones(?).