The function `pandoc.read` is now taking an optional fourth parameter
that specifies the environment in which the parser will be run. Passing
the string `sandbox` as the argument causes the reader to run in a
sandbox, thereby preventing all access to the network and file system.
Closes: #10831
The module provides functions and types for format spec parsing and
processing.
The function `parseFormatSpec` was moved from Text.Pandoc.Extensions to
the new module and renamed to `parseFlavoredFormat`. It now operates in
a PandocMonad and is based on the updated types.