diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index f0bd07bda26e9dc8a5f969229b30b0f04aff8f45..ce9bf60481fe7766999c7728b4c44c3d9eeeee0a 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -155,4 +155,5 @@ terminate:
     - python3 -c "import cosmos; cosmos.terminate_droplets_by_name(\"^ci-\", 2)"
   # This job has no `only` (anymore), so will always run. This works around a
   # Gitlab bug: if no job runs at all due to `only`, Gitlab gets confused and
-  # doesn't allow you to merge the MR.
+  # doesn't allow you to merge the MR:
+  # https://docs.gitlab.com/ee/user/project/merge_requests/merge_when_pipeline_succeeds.html#limitations