diff --git a/src/library_gl.js b/src/library_gl.js
index 66a9cc99c8f3a..069d534359d6b 100644
--- a/src/library_gl.js
+++ b/src/library_gl.js
@@ -549,6 +549,11 @@ var LibraryGL = {
     },
 
 #if OFFSCREEN_FRAMEBUFFER
+    enableOffscreenFramebufferAttributes: function(webGLContextAttributes) {
+      webGLContextAttributes.renderViaOffscreenBackBuffer = true;
+      webGLContextAttributes.preserveDrawingBuffer = true;
+    },
+
     // If WebGL is being proxied from a pthread to the main thread, we can't directly render to the WebGL default back buffer
     // because of WebGL's implicit swap behavior. Therefore in such modes, create an offscreen render target surface to
     // which rendering is performed to, and finally flipped to the main screen.
diff --git a/src/library_glfw.js b/src/library_glfw.js
index 683e902d20577..8393d087d177a 100644
--- a/src/library_glfw.js
+++ b/src/library_glfw.js
@@ -998,8 +998,7 @@ var LibraryGLFW = {
         }
 #if OFFSCREEN_FRAMEBUFFER
         // TODO: Make GLFW explicitly aware of whether it is being proxied or not, and set these to true only when proxying is being performed.
-        contextAttributes.renderViaOffscreenBackBuffer = true;
-        contextAttributes.preserveDrawingBuffer = true;
+        GL.enableOffscreenFramebufferAttributes(contextAttributes);
 #endif
         Module.ctx = Browser.createContext(Module['canvas'], true, true, contextAttributes);
       }
diff --git a/src/library_glut.js b/src/library_glut.js
index 260665cc433e5..bc143ddaec427 100644
--- a/src/library_glut.js
+++ b/src/library_glut.js
@@ -566,8 +566,7 @@ var LibraryGLUT = {
     };
 #if OFFSCREEN_FRAMEBUFFER
     // TODO: Make glutCreateWindow explicitly aware of whether it is being proxied or not, and set these to true only when proxying is being performed.
-    contextAttributes.renderViaOffscreenBackBuffer = true;
-    contextAttributes.preserveDrawingBuffer = true;
+    GL.enableOffscreenFramebufferAttributes(contextAttributes);
 #endif
     Module.ctx = Browser.createContext(Module['canvas'], true, true, contextAttributes);
     return Module.ctx ? 1 /* a new GLUT window ID for the created context */ : 0 /* failure */;
diff --git a/src/library_sdl.js b/src/library_sdl.js
index af909cb6c47dc..e5205dfbc26bd 100644
--- a/src/library_sdl.js
+++ b/src/library_sdl.js
@@ -396,8 +396,7 @@ var LibrarySDL = {
 
 #if OFFSCREEN_FRAMEBUFFER
       // TODO: Make SDL explicitly aware of whether it is being proxied or not, and set these to true only when proxying is being performed.
-      webGLContextAttributes.renderViaOffscreenBackBuffer = true;
-      webGLContextAttributes.preserveDrawingBuffer = true;
+      GL.enableOffscreenFramebufferAttributes(webGLContextAttributes);
 #endif
       var ctx = Browser.createContext(canvas, is_SDL_OPENGL, usePageCanvas, webGLContextAttributes);