diff --git a/filament/backend/src/opengl/OpenGLProgram.cpp b/filament/backend/src/opengl/OpenGLProgram.cpp
index 364932764b..885a93f434 100644
--- a/filament/backend/src/opengl/OpenGLProgram.cpp
+++ b/filament/backend/src/opengl/OpenGLProgram.cpp
@@ -94,7 +94,7 @@ vec2 unpackHalf2x16(highp uint v) {
 }
 
 )"};
-                // a good point for insertion is just before the first occurence of an uniform block
+                // a good point for insertion is just before the first occurrence of an uniform block
                 auto pos = temp.find("layout(std140)");
                 if (pos != std::string_view::npos) {
                     temp.insert(pos, unpackHalf2x16);
diff --git a/libs/filamat/src/GLSLPostProcessor.cpp b/libs/filamat/src/GLSLPostProcessor.cpp
index 9dcd6b6610..b2eb53c1dd 100644
--- a/libs/filamat/src/GLSLPostProcessor.cpp
+++ b/libs/filamat/src/GLSLPostProcessor.cpp
@@ -344,6 +344,11 @@ void GLSLPostProcessor::fullOptimization(const TShader& tShader,
         CompilerGLSL glslCompiler(move(spirv));
         glslCompiler.set_common_options(glslOptions);
 
+        if (tShader.getStage() == EShLangFragment && !glslOptions.es) {
+            // enable GL_ARB_shading_language_packing if available
+            glslCompiler.add_header_line("#extension GL_ARB_shading_language_packing : enable");
+        }
+
         if (tShader.getStage() == EShLangFragment && glslOptions.es) {
             for (auto i : config.glsl.subpassInputToColorLocation) {
                 glslCompiler.remap_ext_framebuffer_fetch(i.first, i.second, true);
diff --git a/libs/filamat/src/shaders/CodeGenerator.cpp b/libs/filamat/src/shaders/CodeGenerator.cpp
index d05c81eda1..61bb0a6172 100644
--- a/libs/filamat/src/shaders/CodeGenerator.cpp
+++ b/libs/filamat/src/shaders/CodeGenerator.cpp
@@ -64,6 +64,7 @@ io::sstream& CodeGenerator::generateProlog(io::sstream& out, ShaderType type,
                 out << "#version 450 core\n\n";
             } else {
                 out << "#version 410 core\n\n";
+                out << "#extension GL_ARB_shading_language_packing : enable\n\n";
             }
             break;
     }