diff --git a/.changeset/pretty-pans-exist.md b/.changeset/pretty-pans-exist.md
new file mode 100644
index 0000000000..e9ccdda0e0
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+++ b/.changeset/pretty-pans-exist.md
@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-app': patch
+---
+
+Added missing default `SignInPageExtension` which by default uses guest auth, missing `ApiExtensions` for `scmAuth`