diff --git a/development/autotests/invertedTests b/development/autotests/invertedTests
index f31a91358f..b39db446b8 100644
--- a/development/autotests/invertedTests
+++ b/development/autotests/invertedTests
@@ -99,6 +99,15 @@ export/export/latex/LongestLabelWithUnderscore.*
 # if they contain non-ASCII characters)
 export/doc/(es|fr)/Additional_pdf4_texF
 
+#10394 Do not error on missing characters in "nullfont".
+# "LaTeXing" seminar fails (except for LuaTeX) with 
+#    Missing character: There is no 0 in font nullfont!
+# due to a bug in PGF (https://sourceforge.net/p/pgf/bugs/314/)
+# However, these warnings can be safely ignored as PGF deliberately uses
+# "nullfont" to suppress output.
+#   http://tex.stackexchange.com/questions/121154/tikzpicture-options-causing-there-is-no-in-font-nullfont
+export/examples/(|fr/)seminar_.*(dvi|pdf|pdf[2-4]).*
+
 
 Sublabel: ert
 #
diff --git a/development/autotests/unreliableTests b/development/autotests/unreliableTests
index 192607ac76..4bcc1d2f39 100644
--- a/development/autotests/unreliableTests
+++ b/development/autotests/unreliableTests
@@ -50,9 +50,6 @@ Sublabel: erratic
 #################
 # Tests depending on local configuration, or the phase of the moon.
 
-# for unknonwn reasons, seminar fails at some places:
-export/examples/(|fr/)seminar_.*(dvi|pdf).*
-
 # Export fails the first time but works the second time. (Why?)
 export/doc/es/Customization_pdf4_texF
 
@@ -76,10 +73,10 @@ Sublabel: wrong_output
 # These tests are actually not "unreliable" (different result for different
 # runs) but *invalid* (not measuring what they should measure).
 
-# seminar.sty uses Postscript specials
-# -> wrong output with pdflatex/LuaTeX and DVI (missing landscape slides).
-export/examples/(|fr/)seminar_pdf[25].*
-export/examples/(|fr/)seminar_dvi.*
+# seminar.sty uses Postscript specials or PGF
+# -> wrong output with DVI (missing landscape slides).
+#    (currently) wrong output with LuaTeX (scaled with 0.5)
+export/examples/(|fr/)seminar_(dvi|pdf5).*
 
 # Babel-Spanish uses Babel's "strings" feature to define
 # separate auto-strings using UTF-8 literals.