--- qtwebkit-5.212.0-alpha4/Source/WebCore/css/makegrammar.pl.orig	2020-03-04 18:16:37.000000000 +0100
+++ qtwebkit-5.212.0-alpha4/Source/WebCore/css/makegrammar.pl	2020-12-21 12:42:44.729244719 +0100
@@ -92,6 +92,16 @@
 print HEADER "#endif\n";
 close HEADER;
 
+rename "$fileBase.cpp", "$fileBase.cpp.in" or die;
+open CPPIN, "<$fileBase.cpp.in" or die;
+open CPPOUT, ">$fileBase.cpp" or die;
+while (<CPPIN>) {
+    s/"${filename}\.(cpp\.h|hpp)"/"${filename}.h"/;
+    print CPPOUT;
+}
+close CPPIN;
+close CPPOUT;
+
 unlink("$fileBase.cpp.h");
 unlink("$fileBase.hpp");