diff --git a/master/master.cfg b/master/master.cfg
index d11469af..903e5a72 100644
--- a/master/master.cfg
+++ b/master/master.cfg
@@ -366,6 +366,7 @@ for branch_num, (git_url, branchname, git_branch) in enumerate(git_branches):
                 # on that.
                 treeStableTimer=1 * 60 * 60,  # h * m * s
                 builderNames=refleakbuildernames,
+                fileIsImportant=is_important_change,
             )
         )