+#
+# These exports correctly fail now that we've switched to polyglossia. Although
+# they compiled without error with babel, the resulting PDFs had gibberish.
+# Note that there is a problem with the LyX-generated preamble in the Russian
+# docs:
+# https://www.mail-archive.com/search?l=mid&q=n0j157%246a1%241%40ger.gmane.org
+export/doc/ru/Intro_pdf5_systemF
+export/doc/ru/Tutorial_pdf5_systemF
+export/doc/el/Intro_pdf5_systemF
+#
+# Inside these two files, we state that they should only be expected
+# to work with pdflatex and possibly lualatex.
+export/examples/PDF-(form)_(dvi.*|pdf[^25]*)
+export/examples/PDF-comment_dvi3_.*F
+#
+export/templates/IUCr-article_pdf4_systemF
+#
+# Gives the following error:
+# # ! Package hpstatement Error: H or P statement "H251"
+# # (hpstatement) is not defined.
+# 1580:export/examples/H-P-statements_pdf5_systemF
+export/examples/H-P-statements_pdf[45]_systemF
+#
+# The math document now depends on the mhchem package which produces wrong
+# output with XeTeX/LuaTeX and both TeX fonts and non-TeX fonts:
+# https://www.mail-archive.com/search?l=mid&q=n0sne9%24iis%241%40ger.gmane.org
+export/doc(|/de|/es|/fr)/Math.*systemF
+export/doc/(|de/|es/|fr/)Math_(dvi3|pdf5)_texF