diff --git a/vncviewer/Viewport.cxx b/vncviewer/Viewport.cxx
index 879c3c5..08ca272 100644
--- a/vncviewer/Viewport.cxx
+++ b/vncviewer/Viewport.cxx
@@ -303,6 +303,9 @@
   if ((w == frameBuffer->width()) && (h == frameBuffer->height()))
     goto end;
 
+  vlog.debug("Resing framebuffer from %dx%d to %dx%d",
+             frameBuffer->width(), frameBuffer->height(), w, h);
+
   newBuffer = new PlatformPixelBuffer(w, h);
   assert(newBuffer);