diff --git a/.github/.OwlBot.lock.yaml b/.github/.OwlBot.lock.yaml
index 127c2cd..da616c9 100644
--- a/.github/.OwlBot.lock.yaml
+++ b/.github/.OwlBot.lock.yaml
@@ -1,3 +1,3 @@
 docker:
   image: gcr.io/repo-automation-bots/owlbot-python:latest
-  digest: sha256:0856ca711da1fd5ec9d6d7da6c50aa0bbf550fb94acb47b55159a640791987bf
+  digest: sha256:c66ba3c8d7bc8566f47df841f98cd0097b28fff0b1864c86f5817f4c8c3e8600
diff --git a/docs/conf.py b/docs/conf.py
index cb6d1e9..d1cb26e 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -363,6 +363,7 @@
     "google.api_core": ("https://googleapis.dev/python/google-api-core/latest/", None,),
     "grpc": ("https://grpc.github.io/grpc/python/", None),
     "proto-plus": ("https://proto-plus-python.readthedocs.io/en/latest/", None),
+    "protobuf": ("https://googleapis.dev/python/protobuf/latest/", None),
 }