diff --git a/modules/libpref/init/StaticPrefList.yaml b/modules/libpref/init/StaticPrefList.yaml
index c1e48a410ecc..83ab0e41a8d9 100644
--- a/modules/libpref/init/StaticPrefList.yaml
+++ b/modules/libpref/init/StaticPrefList.yaml
@@ -13946,7 +13946,7 @@
 # PRIORITY_UPDATE frames.
 - name: network.http.http2.priority_updates
   type: RelaxedAtomicBool
-  value: true
+  value: false
   mirror: always
 
 # This pref controls whether to send the