diff --git a/chat_box/migrations/0016_alter_room_unique_together.py b/chat_box/migrations/0016_alter_room_unique_together.py
new file mode 100644
index 0000000..14b784a
--- /dev/null
+++ b/chat_box/migrations/0016_alter_room_unique_together.py
@@ -0,0 +1,32 @@
+# Generated by Django 3.2.18 on 2024-08-22 03:12
+
+from django.db import migrations, models
+
+
+def remove_duplicates(apps, schema_editor):
+    Room = apps.get_model("chat_box", "Room")
+    seen = set()
+
+    for room in Room.objects.all():
+        pair = (room.user_one_id, room.user_two_id)
+        reverse_pair = (room.user_two_id, room.user_one_id)
+
+        if pair in seen or reverse_pair in seen:
+            room.delete()
+        else:
+            seen.add(pair)
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("chat_box", "0015_room_last_msg_time"),
+    ]
+
+    operations = [
+        migrations.RunPython(remove_duplicates),
+        migrations.AlterUniqueTogether(
+            name="room",
+            unique_together={("user_one", "user_two")},
+        ),
+    ]
diff --git a/chat_box/models.py b/chat_box/models.py
index 476e861..6d86125 100644
--- a/chat_box/models.py
+++ b/chat_box/models.py
@@ -24,6 +24,7 @@ class Room(models.Model):
 
     class Meta:
         app_label = "chat_box"
+        unique_together = ("user_one", "user_two")
 
     @cached_property
     def _cached_info(self):
diff --git a/judge/admin/organization.py b/judge/admin/organization.py
index a6ccc8b..4ac7708 100644
--- a/judge/admin/organization.py
+++ b/judge/admin/organization.py
@@ -33,8 +33,6 @@ class OrganizationAdmin(VersionAdmin):
         "short_name",
         "is_open",
         "about",
-        "organization_image",
-        "logo_override_image",
         "slots",
         "registrant",
         "creation_date",
diff --git a/judge/migrations/0191_deprecate_old_org_image.py b/judge/migrations/0191_deprecate_old_org_image.py
new file mode 100644
index 0000000..76d76f3
--- /dev/null
+++ b/judge/migrations/0191_deprecate_old_org_image.py
@@ -0,0 +1,17 @@
+# Generated by Django 3.2.18 on 2024-08-22 03:12
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("judge", "0190_deprecate_old_notif_fields"),
+    ]
+
+    operations = [
+        migrations.RemoveField(
+            model_name="organization",
+            name="logo_override_image",
+        ),
+    ]
diff --git a/judge/models/profile.py b/judge/models/profile.py
index e601efc..4572b69 100644
--- a/judge/models/profile.py
+++ b/judge/models/profile.py
@@ -111,16 +111,6 @@ class Organization(models.Model):
         blank=True,
     )
     organization_image = models.ImageField(upload_to=organization_image_path, null=True)
-    logo_override_image = models.CharField(
-        verbose_name=_("Logo override image"),
-        default="",
-        max_length=150,
-        blank=True,
-        help_text=_(
-            "This image will replace the default site logo for users "
-            "viewing the organization."
-        ),
-    )
 
     def __contains__(self, item):
         if isinstance(item, int):
diff --git a/judge/views/course.py b/judge/views/course.py
index 8ab5c92..fbda7bd 100644
--- a/judge/views/course.py
+++ b/judge/views/course.py
@@ -48,8 +48,9 @@ def calculate_lessons_progress(profile, lessons):
         num_problems = len(problems)
         percentage = 0
         for val in problem_points.values():
-            score = val["case_points"] / val["case_total"]
-            percentage += score / num_problems
+            if val["case_total"] > 0:
+                score = val["case_points"] / val["case_total"]
+                percentage += score / num_problems
         res[lesson.id] = {
             "achieved_points": percentage * lesson.points,
             "percentage": percentage * 100,
diff --git a/resources/common.js b/resources/common.js
index 47ad467..4533703 100644
--- a/resources/common.js
+++ b/resources/common.js
@@ -538,6 +538,9 @@ function navigateTo(url, reload_container, force_new_page=false) {
                 
                 $(document).prop('title', $(data).filter('title').text());
                 renderKatex($(reload_container)[0]);
+                if ('DjangoPagedown' in window) {
+                  DjangoPagedown.init();
+                }
                 onWindowReady();
                 registerNavList();
                 $('.xdsoft_datetimepicker').hide();