diff --git a/ihatemoney/web.py b/ihatemoney/web.py
index 9e034029..19135a0c 100644
--- a/ihatemoney/web.py
+++ b/ihatemoney/web.py
@@ -112,6 +112,13 @@ def add_project_id(endpoint, values):
         values["project_id"] = g.project.id
 
 
+@main.url_value_preprocessor
+def migrate_session(endpoint, values):
+    if "projects" in session and isinstance(session["projects"], list):
+        # Migrate https://github.com/spiral-project/ihatemoney/pull/1082
+        session["projects"] = {id: name for (id, name) in session["projects"]}
+
+
 @main.url_value_preprocessor
 def set_show_admin_dashboard_link(endpoint, values):
     """Sets the "show_admin_dashboard_link" variable application wide