diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 4273667..9180290 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -63,6 +63,8 @@ schleuder:
     - pip3 install -e .
     - python3 -c 'import os; print(os.listdir(".")); print(); print(os.listdir("test/"))'
     - python3 -m coverage run --rcfile=setup.cfg -m multischleuder --config test/multischleuder.yml --verbose
+    # Run a second time - should be idempotent and not trigger any new mails
+    - python3 -m coverage run --rcfile=setup.cfg -m multischleuder --config test/multischleuder.yml --verbose
     - sleep 5  # wait for mail delivery
     - test/report.sh
     - kill -9 ${API_DAEMON_PID} || true