diff --git a/4134.patch b/4134.patch
new file mode 100644
index 0000000..8f0b0d4
--- /dev/null
+++ b/4134.patch
@@ -0,0 +1,42 @@
+Index: ghc-8.10.4/docs/users_guide/conf.py
+===================================================================
+--- ghc-8.10.4.orig/docs/users_guide/conf.py
++++ ghc-8.10.4/docs/users_guide/conf.py
+@@ -42,9 +42,6 @@ nitpick_ignore = [
+ 
+     ("extension", "DoAndIfThenElse"),
+     ("extension", "RelaxedPolyRec"),
+-
+-    # See #16629
+-    ("extension", "UnliftedFFITypes"),
+ ]
+ 
+ rst_prolog = """
+@@ -100,13 +97,13 @@ htmlhelp_basename = 'GHCUsersGuide'
+ latex_elements = {
+     'inputenc': '',
+     'utf8extra': '',
+-    'preamble': '''
++    'preamble': r'''
+ \usepackage{fontspec}
+ \usepackage{makeidx}
+ \setsansfont{DejaVu Sans}
+ \setromanfont{DejaVu Serif}
+ \setmonofont{DejaVu Sans Mono}
+-\setlength{\\tymin}{45pt}
++\setlength{\tymin}{45pt}
+ ''',
+ }
+ 
+Index: ghc-8.10.4/docs/users_guide/expected-undocumented-flags.txt
+===================================================================
+--- ghc-8.10.4.orig/docs/users_guide/expected-undocumented-flags.txt
++++ ghc-8.10.4/docs/users_guide/expected-undocumented-flags.txt
+@@ -38,7 +38,6 @@
+ -XAutoDeriveTypeable
+ -XDoAndIfThenElse
+ -XDoRec
+--XGHCForeignImportPrim
+ -XGenerics
+ -XImplicitPrelude
+ -XJavaScriptFFI
diff --git a/ghc.changes b/ghc.changes
index 9e89194..bd3383d 100644
--- a/ghc.changes
+++ b/ghc.changes
@@ -1,3 +1,8 @@
+-------------------------------------------------------------------
+Fri Jun 25 10:02:25 UTC 2021 - Ondřej Súkup <mimi.vx@gmail.com>
+
+- add 4134.patch to fix build with Sphinx4 
+
 -------------------------------------------------------------------
 Mon Mar 15 20:33:24 UTC 2021 - Dirk Müller <dmueller@suse.com>
 
diff --git a/ghc.spec b/ghc.spec
index fd81bad..36dd220 100644
--- a/ghc.spec
+++ b/ghc.spec
@@ -80,6 +80,8 @@ Patch35:        ghc-pie.patch
 Patch100:       ghc-8.0.2-Cabal-dynlibdir.patch
 # PATCH-FIX-UPSTREAM buildpath-abi-stability.patch -- debian patch for more stable abi-1
 Patch110:       buildpath-abi-stability.patch
+# PATCH-FIX-UPSTREAM 4134.diff -- documentation fiixes and sphinx4 build fix
+Patch120:       4134.patch
 
 %description
 Haskell is the standard purely functional programming language; the
@@ -192,6 +194,7 @@ except the ghc library, which is installed by the toplevel ghc metapackage.
 %patch35 -p1
 %patch100 -p1
 %patch110 -p1
+%patch120 -p1
 
 %build
 cat > mk/build.mk <<EOF