diff --git a/ext/qt/qtwindow.cc b/ext/qt/qtwindow.cc
index 1151ddc080..62d26b647b 100644
--- a/ext/qt/qtwindow.cc
+++ b/ext/qt/qtwindow.cc
@@ -40,6 +40,9 @@
 #ifndef GL_READ_FRAMEBUFFER
 #define GL_READ_FRAMEBUFFER 0x8CA8
 #endif
+#ifndef GL_DRAW_FRAMEBUFFER
+#define GL_DRAW_FRAMEBUFFER 0x8CA9
+#endif
 
 /**
  * SECTION: