Add viewport note

app.py

@@ -59,6 +59,9 @@ class TheraApp(DualVisionApp):
             <p align="center" style="margin-top: 0px;">
                 <strong>Note: The model has not been trained on input images with JPEG artifacts, so this may not work well.</strong>
             </p>
+            <p align="center" style="margin-top: 0px;">
+                <strong>Also note: Due to limited viewport size in the browser, the effect is best visible for smaller inputs (e.g. 150x150 px).<br>For larger inputs, it makes sense to zoom in or download the result and compare locally. We're working on a better solution for visualization.</strong>
+            </p>
         """
         )