This is mostly for shapepar support, in a rare situation. Fixing this would create a lot of special cases in output_docbook.cpp, i.e. fixing the issue (which will barely happen in real life) would make maintenance much harder.
export/mathmacros/testcases_speed_docbook5
export/mathmacros/testcases_environments_docbook5
export/mathmacros/masterOfSpace_docbook5
+# - Sidebars can be nested in LyX (mostly with shapepar), but not in DocBook.
+export/doc(|/de|/es|/fr|/ja|/ru)/Additional_docbook5
# - Many templates are too complex for automatic conversion to work reliably.
# The resulting documents should still be easy to fully convert into DocBook.
# - AASTeX.