diff --git a/.taskcluster.yml b/.taskcluster.yml
index dcbb262c72..67c0a3b561 100644
--- a/.taskcluster.yml
+++ b/.taskcluster.yml
@@ -155,6 +155,7 @@ tasks:
               - {$eval: 'default_task_definition'}
               - scopes:
                   - ${assume_scope_prefix}:branch:${short_head_branch}
+                  - ${assume_scope_prefix}:pull-request
                 payload:
                   command:
                     - >-