I also noticed that we build display lists/ layers for the entire screen when painting the titlebar. I think we could probably add a parameter to restrict the visible region to the just the titlebar area.

Comment on attachment 667314 [details] [diff] [review] Fix the secondary layer manager code Review of attachment 667314 [details] [diff] [review]: ----------------------------------------------------------------- ::: widget/xpwidgets/nsBaseWidget.cpp @@ +908,5 @@ > } > } > if (mTemporarilyUseBasicLayerManager && !mBasicLayerManager) { > mBasicLayerManager = CreateBasicLayerManager(); > + mBasicLayerManager->SetUserData(&mozilla::gLayerManagerSecondary, nullptr); We really shouldn't use FrameLayerBuilder from here. Define gLayerManagerSecondary in nsIWidget instead. And, this should really be set in the Mac titlebar painting code, not here!

Comment on attachment 669373 [details] [diff] [review] Fix the secondary layer manager code Review of attachment 669373 [details] [diff] [review]: ----------------------------------------------------------------- ::: widget/cocoa/nsChildView.mm @@ +2390,5 @@ > > // Title bar drawing only works if we really draw into aContext, which only > // the basic layer manager will do. > nsBaseWidget::AutoUseBasicLayerManager setupLayerManager(mGeckoChild); > + mGeckoChild->GetLayerManager()->SetUserData(&gLayerManagerSecondary, nullptr); If I read nsBaseWidget::GetLayerManager right, on Macs where GL compositing is not enabled (are there any still?) this will use the same layer manager as for normal compositing, won't it? ::: widget/nsIWidget.h @@ +36,5 @@ > class ViewWrapper; > class nsIWidgetListener; > class nsIntRegion; > > +extern uint8_t gLayerManagerSecondary; Make it a member of nsIWidget. And put the definition in nsBaseWidget.cpp instead of FrameLayerBuilder. And wrap it in an accessor "static void* nsIWidget::SecondaryLayerManagerKey()".

Fixed by bug 795674

Bug 795674 was uplifted to Aurora.