widen-automatically

widen-automatically is a variable defined in `simple.el'.
Its value is

t

Documentation:
Non-nil means it is ok for commands to call `widen' when they want to.
Some commands will do this in order to go to positions outside
the current accessible part of the buffer.

If `widen-automatically' is nil, these commands will do something else
as a fallback, and won't change the buffer bounds.