diff -r 9c008b241362 -r 4c248180e576 firefox-add-kde.js-in-order-to-survive-PGO-build.patch
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/firefox-add-kde.js-in-order-to-survive-PGO-build.patch	Mon Jul 08 12:56:52 2019 +0200
@@ -0,0 +1,34 @@
+From 89767f5dd97e69d7e9189e5603647645818d27d6 Mon Sep 17 00:00:00 2001
+From: marxin <mliska@suse.cz>
+Date: Thu, 29 Nov 2018 10:07:29 +0100
+Subject: [PATCH 2/3] Add kde.js in order to survive PGO build.
+
+---
+ browser/app/Makefile.in | 1 +
+ kde.js                  | 2 ++
+ 2 files changed, 3 insertions(+)
+ create mode 100644 kde.js
+
+diff --git a/browser/app/Makefile.in b/browser/app/Makefile.in
+index 4129aa43fb91..c9950895d520 100644
+--- a/browser/app/Makefile.in
++++ b/browser/app/Makefile.in
+@@ -57,6 +57,7 @@ endif
+ libs:: $(srcdir)/profile/channel-prefs.js
+ 	$(NSINSTALL) -D $(DIST)/bin/defaults/pref
+ 	$(call py_action,preprocessor,-Fsubstitution $(PREF_PPFLAGS) $(ACDEFINES) $^ -o $(DIST)/bin/defaults/pref/channel-prefs.js)
++	cp $(topsrcdir)/kde.js $(DIST)/bin/defaults/pref/kde.js
+ 
+ ifeq (cocoa,$(MOZ_WIDGET_TOOLKIT))
+ 
+diff --git a/kde.js b/kde.js
+new file mode 100644
+index 000000000000..b0d3e5d20437
+--- /dev/null
++++ b/kde.js
+@@ -0,0 +1,2 @@
++pref("browser.preferences.instantApply", false);
++pref("browser.backspace_action", 0);
+-- 
+2.19.1
+