diff --git a/panda/src/glstuff/glGraphicsStateGuardian_src.cxx b/panda/src/glstuff/glGraphicsStateGuardian_src.cxx
index fc304d8a96..24bd54134d 100644
--- a/panda/src/glstuff/glGraphicsStateGuardian_src.cxx
+++ b/panda/src/glstuff/glGraphicsStateGuardian_src.cxx
@@ -14460,6 +14460,7 @@ do_extract_texture_data(CLP(TextureContext) *gtc) {
     break;
   case GL_LUMINANCE:
 #ifndef OPENGLES
+  case GL_LUMINANCE8_EXT:
   case GL_LUMINANCE16:
   case GL_LUMINANCE16F_ARB:
 #endif