diff --git a/development/autotests/invertedTests b/development/autotests/invertedTests
index f377885fcb..c52d7e2617 100644
--- a/development/autotests/invertedTests
+++ b/development/autotests/invertedTests
@@ -20,12 +20,6 @@ Sublabel: todo
 # XeTeX artifact? works with LuaTeX, explore:
 export/doc/(|de/|es/|fr/)EmbeddedObjects_pdf4_systemF
 
-# WARNING: unknown cross-reference-class `hyperindexformat'! (ignored)
-# ! Undefined control sequence.
-# Text:  ...e Ã<8d>ndice alfabético}{75}{section*.10}
-# Text inside 'Index Entries'?
-export/doc/es/(EmbeddedObjects|Math|UserGuide)_(dvi3|pdf5)_texF
-
 # iconv fails, if a nomenclature inset contains an uncodable character
 export/export/latex/iconv-error-nomenclature_pdf2
 
diff --git a/development/autotests/unreliableTests b/development/autotests/unreliableTests
index 32b2412450..3b04a051ae 100644
--- a/development/autotests/unreliableTests
+++ b/development/autotests/unreliableTests
@@ -160,15 +160,7 @@ export/examples/(|fr/)Presentations/Seminar_(dvi|pdf).*
 # Babel-Spanish uses UTF-8 encoded strings if it detects Xe/LuaTeX.
 # With "language default" (=="latin9"), Babel strings  come out wrong
 # when compiling with Xe/LuaTeX and TeX-fonts.
-# - The problem is generic to all Spanish documents but only manifests itself
-#   if Babel strings with non-ASCII chars are actually used
-#   (the ToC heading, e.g., becomes "ÃŊndice" instead of "Índice").
-# - In some cases, export fails
-#   (see invertedTests, some more tests fail with TeXLive versions < 18).
-# Should we set inputenc to utf8 in the documents to work around the problem?
-# (Changing the default in lib/languages requires more tests for utf8 first.)
-export/examples/es/.*_(pdf5|dvi3)_texF
-export/doc/es/.*_(pdf5|dvi3)_texF
+export/export/latex/es_auto-legacy_texF
 
 # since TL18, Babel-Ukrainean uses UTF-8 if it detects Xe/LuaTeX (for "\date").
 # * garbled output with LuaTeX + TeX fonts (since TL18)
diff --git a/lib/doc/es/Additional.lyx b/lib/doc/es/Additional.lyx
index fe032f6ff6..2b408d0fba 100644
--- a/lib/doc/es/Additional.lyx
+++ b/lib/doc/es/Additional.lyx
@@ -40,7 +40,7 @@ shapepar
 \maintain_unincluded_children false
 \language spanish
 \language_package default
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "lmodern" "default"
 \font_sans "lmss" "default"
diff --git a/lib/doc/es/Customization.lyx b/lib/doc/es/Customization.lyx
index 6eb7fdcae2..712f7f0530 100644
--- a/lib/doc/es/Customization.lyx
+++ b/lib/doc/es/Customization.lyx
@@ -43,7 +43,7 @@ logicalmkup
 \maintain_unincluded_children false
 \language spanish
 \language_package default
-\inputencoding auto
+\inputencoding utf8
 \fontencoding auto
 \font_roman "lmodern" "default"
 \font_sans "lmss" "default"
diff --git a/lib/doc/es/DocumentoPostizo1.lyx b/lib/doc/es/DocumentoPostizo1.lyx
index d7c1e79164..58bd73b8f9 100644
--- a/lib/doc/es/DocumentoPostizo1.lyx
+++ b/lib/doc/es/DocumentoPostizo1.lyx
@@ -9,7 +9,7 @@
 \maintain_unincluded_children false
 \language spanish
 \language_package default
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "default" "default"
 \font_sans "default" "default"
diff --git a/lib/doc/es/DocumentoPostizo2.lyx b/lib/doc/es/DocumentoPostizo2.lyx
index 1faabc1a4e..a95c3c4884 100644
--- a/lib/doc/es/DocumentoPostizo2.lyx
+++ b/lib/doc/es/DocumentoPostizo2.lyx
@@ -9,7 +9,7 @@
 \maintain_unincluded_children false
 \language spanish
 \language_package default
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "default" "default"
 \font_sans "default" "default"
diff --git a/lib/doc/es/EmbeddedObjects.lyx b/lib/doc/es/EmbeddedObjects.lyx
index 29813c8309..709c62c9f2 100644
--- a/lib/doc/es/EmbeddedObjects.lyx
+++ b/lib/doc/es/EmbeddedObjects.lyx
@@ -164,11 +164,11 @@ varwidth
 \maintain_unincluded_children false
 \language spanish
 \language_package babel
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "lmodern" "default"
-\font_sans "lmss" "default"
-\font_typewriter "lmtt" "default"
+\font_sans "default" "default"
+\font_typewriter "default" "default"
 \font_math "auto" "auto"
 \font_default_family default
 \use_non_tex_fonts false
diff --git a/lib/doc/es/Formula-numbering.lyx b/lib/doc/es/Formula-numbering.lyx
index 0a101eb2ae..7636f497d0 100644
--- a/lib/doc/es/Formula-numbering.lyx
+++ b/lib/doc/es/Formula-numbering.lyx
@@ -47,7 +47,7 @@
 \maintain_unincluded_children false
 \language spanish
 \language_package default
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "default" "default"
 \font_sans "default" "default"
diff --git a/lib/doc/es/Intro.lyx b/lib/doc/es/Intro.lyx
index 6607dc7a59..67d282059d 100644
--- a/lib/doc/es/Intro.lyx
+++ b/lib/doc/es/Intro.lyx
@@ -29,7 +29,7 @@
 \maintain_unincluded_children false
 \language spanish
 \language_package default
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "palatino" "default"
 \font_sans "helvet" "default"
diff --git a/lib/doc/es/Math.lyx b/lib/doc/es/Math.lyx
index dcb95c2916..0b07211744 100644
--- a/lib/doc/es/Math.lyx
+++ b/lib/doc/es/Math.lyx
@@ -140,7 +140,7 @@ subequations
 \maintain_unincluded_children false
 \language spanish
 \language_package babel
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "lmodern" "default"
 \font_sans "lmss" "default"
diff --git a/lib/doc/es/Shortcuts.lyx b/lib/doc/es/Shortcuts.lyx
index eb827d578c..d71b497541 100644
--- a/lib/doc/es/Shortcuts.lyx
+++ b/lib/doc/es/Shortcuts.lyx
@@ -9,7 +9,7 @@
 \maintain_unincluded_children false
 \language spanish
 \language_package default
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "default" "default"
 \font_sans "default" "default"
diff --git a/lib/doc/es/Tutorial.lyx b/lib/doc/es/Tutorial.lyx
index 86dc96c8c2..00fa33d3ca 100644
--- a/lib/doc/es/Tutorial.lyx
+++ b/lib/doc/es/Tutorial.lyx
@@ -9,7 +9,7 @@
 \maintain_unincluded_children false
 \language spanish
 \language_package babel
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "palatino" "default"
 \font_sans "helvet" "default"
diff --git a/lib/doc/es/UserGuide.lyx b/lib/doc/es/UserGuide.lyx
index d548e887a1..16b0ef5e16 100644
--- a/lib/doc/es/UserGuide.lyx
+++ b/lib/doc/es/UserGuide.lyx
@@ -56,11 +56,11 @@ enumitem
 \maintain_unincluded_children false
 \language spanish
 \language_package babel
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "lmodern" "default"
-\font_sans "lmss" "default"
-\font_typewriter "lmtt" "default"
+\font_sans "default" "default"
+\font_typewriter "default" "default"
 \font_math "auto" "auto"
 \font_default_family default
 \use_non_tex_fonts false
diff --git a/lib/examples/es/Books/Tufte_Book.lyx b/lib/examples/es/Books/Tufte_Book.lyx
index daa70f1cc2..f25d9ae8af 100644
--- a/lib/examples/es/Books/Tufte_Book.lyx
+++ b/lib/examples/es/Books/Tufte_Book.lyx
@@ -13,7 +13,7 @@
 \maintain_unincluded_children false
 \language spanish
 \language_package default
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "default" "default"
 \font_sans "default" "default"
diff --git a/lib/examples/es/Curricula_Vitae/Modern_CV.lyx b/lib/examples/es/Curricula_Vitae/Modern_CV.lyx
index cb9dd10517..b4c903b07b 100644
--- a/lib/examples/es/Curricula_Vitae/Modern_CV.lyx
+++ b/lib/examples/es/Curricula_Vitae/Modern_CV.lyx
@@ -12,7 +12,7 @@
 \maintain_unincluded_children false
 \language spanish
 \language_package default
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "default" "default"
 \font_sans "default" "default"
diff --git a/lib/examples/es/Example_%28LyXified%29.lyx b/lib/examples/es/Example_%28LyXified%29.lyx
index 21b3a79e4d..cd37d6ba2f 100644
--- a/lib/examples/es/Example_%28LyXified%29.lyx
+++ b/lib/examples/es/Example_%28LyXified%29.lyx
@@ -9,7 +9,7 @@
 \maintain_unincluded_children false
 \language spanish
 \language_package default
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "default" "default"
 \font_sans "default" "default"
diff --git a/lib/examples/es/Example_%28raw%29.lyx b/lib/examples/es/Example_%28raw%29.lyx
index aa2d019608..51853d156f 100644
--- a/lib/examples/es/Example_%28raw%29.lyx
+++ b/lib/examples/es/Example_%28raw%29.lyx
@@ -9,7 +9,7 @@
 \maintain_unincluded_children false
 \language spanish
 \language_package default
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "default" "default"
 \font_sans "default" "default"
diff --git a/lib/examples/es/Graphics_and_Insets/Itemize_Bullets.lyx b/lib/examples/es/Graphics_and_Insets/Itemize_Bullets.lyx
index f2db9e0a76..a0778971ab 100644
--- a/lib/examples/es/Graphics_and_Insets/Itemize_Bullets.lyx
+++ b/lib/examples/es/Graphics_and_Insets/Itemize_Bullets.lyx
@@ -12,7 +12,7 @@
 \maintain_unincluded_children false
 \language spanish
 \language_package default
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "default" "default"
 \font_sans "default" "default"
diff --git a/lib/examples/es/Handouts/Tufte_Handout.lyx b/lib/examples/es/Handouts/Tufte_Handout.lyx
index b3aaf04555..88568e860e 100644
--- a/lib/examples/es/Handouts/Tufte_Handout.lyx
+++ b/lib/examples/es/Handouts/Tufte_Handout.lyx
@@ -9,7 +9,7 @@
 \maintain_unincluded_children false
 \language spanish
 \language_package default
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "default" "default"
 \font_sans "helvet" "default"
diff --git a/lib/examples/es/Modules/Linguistics.lyx b/lib/examples/es/Modules/Linguistics.lyx
index 10b11719c7..652c01d866 100644
--- a/lib/examples/es/Modules/Linguistics.lyx
+++ b/lib/examples/es/Modules/Linguistics.lyx
@@ -41,7 +41,7 @@ linguistics
 \maintain_unincluded_children false
 \language spanish
 \language_package default
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "lmodern" "FreeSerif"
 \font_sans "default" "FreeSans"
diff --git a/lib/templates/es/Presentations/Beamer.lyx b/lib/templates/es/Presentations/Beamer.lyx
index cfa18144c7..2972deeb2c 100644
--- a/lib/templates/es/Presentations/Beamer.lyx
+++ b/lib/templates/es/Presentations/Beamer.lyx
@@ -16,7 +16,7 @@
 \maintain_unincluded_children false
 \language spanish
 \language_package default
-\inputencoding auto
+\inputencoding utf8
 \fontencoding global
 \font_roman "lmodern" "default"
 \font_sans "lmss" "default"