--- a/gfx/thebes/gfxPrefs.h
+++ b/gfx/thebes/gfxPrefs.h
@@ -502,17 +502,17 @@ private:
   DECL_GFX_PREF(Once, "gfx.use-iosurface-textures",            UseIOSurfaceTextures, bool, false);
   DECL_GFX_PREF(Once, "gfx.use-mutex-on-present",              UseMutexOnPresent, bool, false);
   DECL_GFX_PREF(Once, "gfx.use-surfacetexture-textures",       UseSurfaceTextureTextures, bool, false);
 
   DECL_GFX_PREF(Live, "gfx.vsync.collect-scroll-transforms",   CollectScrollTransforms, bool, false);
   DECL_GFX_PREF(Once, "gfx.vsync.compositor.unobserve-count",  CompositorUnobserveCount, int32_t, 10);
 
   DECL_GFX_PREF(Once, "gfx.webrender.all",                     WebRenderAll, bool, false);
-  DECL_GFX_PREF(Once, "gfx.webrender.async-scene-build",       WebRenderAsyncSceneBuild, bool, false);
+  DECL_OVERRIDE_PREF(Once, "gfx.webrender.async-scene-build",  WebRenderAsyncSceneBuild, gfxPrefs::WebRenderAll());
   DECL_GFX_PREF(Once, "gfx.webrender.enabled",                 WebRenderEnabledDoNotUseDirectly, bool, false);
   DECL_GFX_PREF(Live, "gfx.webrender.blob-images",             WebRenderBlobImages, bool, true);
   DECL_GFX_PREF(Live, "gfx.webrender.blob.invalidation",       WebRenderBlobInvalidation, bool, false);
   DECL_GFX_PREF(Live, "gfx.webrender.highlight-painted-layers",WebRenderHighlightPaintedLayers, bool, false);
   DECL_GFX_PREF(Live, "gfx.webrender.hit-test",                WebRenderHitTest, bool, true);
 
   // Use vsync events generated by hardware
   DECL_GFX_PREF(Once, "gfx.work-around-driver-bugs",           WorkAroundDriverBugs, bool, true);

--- a/modules/libpref/init/all.js
+++ b/modules/libpref/init/all.js
@@ -849,17 +849,17 @@ pref("gfx.webrender.dcomp-win.enabled", 
 pref("gfx.webrender.program-binary", true);
 #endif
 
 #ifdef XP_MACOSX
 pref("gfx.compositor.glcontext.opaque", false);
 #endif
 
 pref("gfx.webrender.highlight-painted-layers", false);
-pref("gfx.webrender.async-scene-build", false);
+pref("gfx.webrender.async-scene-build", 2);
 pref("gfx.webrender.blob-images", true);
 pref("gfx.webrender.blob.invalidation", true);
 pref("gfx.webrender.hit-test", true);
 
 // WebRender debugging utilities.
 pref("gfx.webrender.debug.texture-cache", false);
 pref("gfx.webrender.debug.render-targets", false);
 pref("gfx.webrender.debug.alpha-primitives", false);