diff --git a/src/mesa/main/context.c b/src/mesa/main/context.c
index 34da16b88f4..04ef4d500d8 100644
--- a/src/mesa/main/context.c
+++ b/src/mesa/main/context.c
@@ -1765,6 +1765,10 @@ _mesa_make_current( struct gl_context *newCtx,
 
          check_init_viewport(newCtx, drawBuffer->Width, drawBuffer->Height);
       }
+      else {
+         _mesa_reference_framebuffer(&newCtx->WinSysDrawBuffer, NULL);
+         _mesa_reference_framebuffer(&newCtx->WinSysReadBuffer, NULL);
+      }
 
       if (newCtx->FirstTimeCurrent) {
          handle_first_current(newCtx);