diff --git a/changelogs/unreleased/51651-fill-pipeline-source-for-external-pipelines.yml b/changelogs/unreleased/51651-fill-pipeline-source-for-external-pipelines.yml
new file mode 100644
index 00000000000..6720430e5fc
--- /dev/null
+++ b/changelogs/unreleased/51651-fill-pipeline-source-for-external-pipelines.yml
@@ -0,0 +1,5 @@
+---
+title: Retroactively fill pipeline source for external pipelines.
+merge_request: 21814
+author:
+type: other