diff --git a/map/models.py b/map/models.py
index bc4e6e7..48a157d 100644
--- a/map/models.py
+++ b/map/models.py
@@ -13,7 +13,12 @@ class BaseModel(models.Model):
 
 
 class Friend(AbstractUser):
-    pass
+    def get_display_name(self):
+        display_name = super().get_full_name()
+        if not display_name:
+            display_name = self.username
+
+        return display_name
 
 
 class FriendLocation(BaseModel):
@@ -32,5 +37,14 @@ class FriendLocation(BaseModel):
         return str(self.longitude)
 
     def __str__(self):
-        return f'{self.friend.get_full_name()} from {self.start_date} to {self.end_date}'
+        return f'{self.friend.get_display_name()} from {self.start_date} to {self.end_date}'
+
+    @property
+    def safe_html(self):
+        html = f'<strong>{self.friend.get_display_name()}</strong>'
+        if self.start_date:
+            html += f' from {self.start_date}'
+        if self.end_date:
+            html += f' until {self.end_date}'
+        return html
 
diff --git a/map/templates/map/map.html b/map/templates/map/map.html
index 3adeb67..5cf3ec7 100644
--- a/map/templates/map/map.html
+++ b/map/templates/map/map.html
@@ -21,9 +21,10 @@
         L.tileLayer('https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
             attribution: '&copy; <a href="https://www.openstreetmap.org/copyright">OpenStreetMap</a> contributors'
         }).addTo(map);
+        let marker = null;
         {% for location in locations %}
-            let marker = L.marker([{{ location.latitude_str }}, {{ location.longitude_str }}]).addTo(map);
-            marker.bindPopup("<strong>{{ location.friend.get_full_name }}</strong> from {{ location.start_date }} until {{ location.end_date }}");
+            marker = L.marker([{{ location.latitude_str }}, {{ location.longitude_str }}]).addTo(map);
+            marker.bindPopup("{{ location.safe_html|safe }}");
         {% endfor %}
     </script>
 {% endblock %}