--- a/tests/test-rebase-collapse.t	Tue Apr 27 14:59:45 2021 -0700
+++ b/tests/test-rebase-collapse.t	Thu Feb 11 15:11:10 2021 -0800
@@ -550,7 +550,7 @@
   
   $ hg rebase --collapse -r 1 -d 0
   abort: cannot rebase changeset with children
-  (use --keep to keep original changesets)
+  (see 'hg help evolution.instability')
   [10]
 
 Test collapsing in place