diff --git a/build-nspr.patch b/build-nspr.patch
new file mode 100644
index 0000000..acb67af
--- /dev/null
+++ b/build-nspr.patch
@@ -0,0 +1,28 @@
+diff -up firefox-80.0/dom/system/IOUtils.cpp.nspr-build firefox-80.0/dom/system/IOUtils.cpp
+--- firefox-80.0/dom/system/IOUtils.cpp.nspr-build	2020-08-19 17:38:00.895018639 +0200
++++ firefox-80.0/dom/system/IOUtils.cpp	2020-08-19 17:38:09.965978725 +0200
+@@ -14,9 +14,9 @@
+ #include "mozilla/Services.h"
+ #include "mozilla/Span.h"
+ #include "mozilla/TextUtils.h"
+-#include "nspr/prio.h"
+-#include "nspr/private/pprio.h"
+-#include "nspr/prtypes.h"
++#include "prio.h"
++#include "private/pprio.h"
++#include "prtypes.h"
+ #include "nsDirectoryServiceDefs.h"
+ #include "nsIFile.h"
+ #include "nsIGlobalObject.h"
+diff -up firefox-80.0/dom/system/IOUtils.h.nspr-build firefox-80.0/dom/system/IOUtils.h
+--- firefox-80.0/dom/system/IOUtils.h.nspr-build	2020-08-17 22:13:15.000000000 +0200
++++ firefox-80.0/dom/system/IOUtils.h	2020-08-19 17:20:33.332711771 +0200
+@@ -14,7 +14,7 @@
+ #include "mozilla/dom/TypedArray.h"
+ #include "mozilla/ErrorResult.h"
+ #include "mozilla/MozPromise.h"
+-#include "nspr/prio.h"
++#include "prio.h"
+ #include "nsIAsyncShutdown.h"
+ #include "nsISerialEventTarget.h"
+ #include "nsLocalFile.h"
diff --git a/firefox.spec b/firefox.spec
index e33b07d..ec121ac 100644
--- a/firefox.spec
+++ b/firefox.spec
@@ -158,6 +158,7 @@ Patch47:        fedora-shebang-build.patch
 Patch48:        build-arm-wasm.patch
 Patch49:        build-arm-libaom.patch
 #Patch50:        Bug-1610814-Fix-NEON-compile-error-with-gcc-and-RGB-.patch
+Patch51:        build-nspr.patch
 
 # Fedora specific patches
 Patch215:        firefox-enable-addons.patch
@@ -362,6 +363,7 @@ This package contains results of tests executed during build.
 %patch48 -p1 -b .build-arm-wasm
 %patch49 -p1 -b .build-arm-libaom
 #%patch50 -p1 -b .build-arm-SwizzleNEON
+%patch51 -p1 -b .build-nspr
 
 # Fedora patches
 %patch215 -p1 -b .addons