diff --git a/webapp_media.py b/webapp_media.py
index f6034805..052061ea 100644
--- a/webapp_media.py
+++ b/webapp_media.py
@@ -83,15 +83,17 @@ def _addEmbeddedVideoFromSites(translate: {}, content: str,
             return content
 
     if '"https://' in content:
-        # A selection of the current larger peertube sites, mostly
-        # French and German language
-        # These have been chosen based on reported numbers of users
-        # and the content of each has not been reviewed, so mileage could vary
-        # Also see https://peertube_isolation.frama.io/list/ for
-        # adversarial instances
         if peertubeInstances:
             peerTubeSites = peertubeInstances
         else:
+            # A default selection of the current larger peertube sites,
+            # mostly French and German language
+            # These have been chosen based on reported numbers of users
+            # and the content of each has not been reviewed, so mileage
+            # could vary
+            # Also see https://peertube_isolation.frama.io/list/ for
+            # adversarial instances. Nothing in that list should be
+            # in the defaults below.
             peerTubeSites = ('peertube.mastodon.host', 'share.tube',
                              'tube.tr4sk.me', 'videos.elbinario.net',
                              'hkvideo.live',