org-export-async-init-file

org-export-async-init-file is a variable defined in `ox.el'.
Its value is

nil

Documentation:
File used to initialize external export process.
Value must be an absolute file name. It defaults to user's
initialization file. Though, a specific configuration makes the
process faster and the export more portable.

You can customize this variable.

This variable was introduced, or its default value was changed, in version 24.4 of Emacs.