fontforge/fontforge — pull request #1653 by frank-trampe (2014-08-12 23:42:15+00:00)
Title: Handle foreign data in U. F. O..

This uses the PyTuple, which has no matching entity in X. M. L. as a special container for unrecognized data in python_persistent, allowing FontForge to round-trip that data in the top-level lib.plist and in the lib data for individual glifs.