1 files changed, 11 insertions, 0 deletions
diff --git a/dom/canvas/HostWebGLContext.cpp b/dom/canvas/HostWebGLContext.cpp
index 11051c756f..4eea15773a 100644
--- a/dom/canvas/HostWebGLContext.cpp
+++ b/dom/canvas/HostWebGLContext.cpp
@@ -180,6 +180,17 @@ void HostWebGLContext::CreateSync(const ObjectId id) {
     return;
   }
   slot = GetWebGL2Context()->FenceSync(LOCAL_GL_SYNC_GPU_COMMANDS_COMPLETE, 0);
+
+  if (!slot) return;
+
+  slot->OnCompleteTaskAdd([host = WeakPtr{this}, id]() {
+    if (!host) return;
+    if (host->mOwnerData.inProcess) {
+      host->mOwnerData.inProcess->OnSyncComplete(id);
+    } else if (host->mOwnerData.outOfProcess) {
+      (void)host->mOwnerData.outOfProcess->SendOnSyncComplete(id);
+    }
+  });
 }
 
 void HostWebGLContext::CreateTexture(const ObjectId id) {