diff --git a/python/mozbuild/mozbuild/test/test_manifest.py b/python/mozbuild/mozbuild/test/test_manifest.py
index c50cef9ec6d8..61ea72f6373e 100644
--- a/python/mozbuild/mozbuild/test/test_manifest.py
+++ b/python/mozbuild/mozbuild/test/test_manifest.py
@@ -41,10 +41,7 @@ class TestManifest(unittest.TestCase):
                 "revision": "AA001122334455",
                 "url": "https://www.cairographics.org/",
             },
-            "bugzilla": {
-                "component": "Graphics",
-                "product": "Core",
-            },
+            "bugzilla": {"component": "Graphics", "product": "Core"},
         }
 
         self.process_test_vectors(
@@ -104,10 +101,7 @@ bugzilla:
                             "revision": "AA001122334455",
                             "url": "https://www.cairographics.org/",
                         },
-                        "bugzilla": {
-                            "component": "Graphics",
-                            "product": "Core",
-                        },
+                        "bugzilla": {"component": "Graphics", "product": "Core"},
                         "updatebot": {
                             "maintainer-phab": "tjr",
                             "maintainer-bz": "a@example.com",
@@ -145,10 +139,7 @@ updatebot:
                             "revision": "AA001122334455",
                             "url": "https://www.cairographics.org/",
                         },
-                        "bugzilla": {
-                            "component": "Graphics",
-                            "product": "Core",
-                        },
+                        "bugzilla": {"component": "Graphics", "product": "Core"},
                         "vendoring": {
                             "url": "https://example.com",
                             "source-hosting": "gitlab",
@@ -156,6 +147,7 @@ updatebot:
                         "updatebot": {
                             "maintainer-phab": "tjr",
                             "maintainer-bz": "a@example.com",
+                            "tracking": "commit",
                             "tasks": [{"type": "commit-alert"}],
                         },
                     },
@@ -196,10 +188,7 @@ updatebot:
                             "revision": "AA001122334455",
                             "url": "https://www.cairographics.org/",
                         },
-                        "bugzilla": {
-                            "component": "Graphics",
-                            "product": "Core",
-                        },
+                        "bugzilla": {"component": "Graphics", "product": "Core"},
                         "vendoring": {
                             "url": "https://example.com",
                             "source-hosting": "gitlab",
@@ -207,11 +196,9 @@ updatebot:
                         "updatebot": {
                             "maintainer-phab": "tjr",
                             "maintainer-bz": "a@example.com",
+                            "tracking": "commit",
                             "tasks": [
-                                {
-                                    "type": "commit-alert",
-                                    "frequency": "release",
-                                },
+                                {"type": "commit-alert", "frequency": "release"},
                                 {
                                     "type": "vendoring",
                                     "branch": "foo",
@@ -244,6 +231,7 @@ bugzilla:
 updatebot:
   maintainer-phab: tjr
   maintainer-bz: a@example.com
+  tracking: commit
   tasks:
     - type: commit-alert
       frequency: release
@@ -267,10 +255,7 @@ updatebot:
                             "revision": "AA001122334455",
                             "url": "https://www.cairographics.org/",
                         },
-                        "bugzilla": {
-                            "component": "Graphics",
-                            "product": "Core",
-                        },
+                        "bugzilla": {"component": "Graphics", "product": "Core"},
                         "vendoring": {
                             "url": "https://example.com",
                             "source-hosting": "gitlab",
@@ -278,6 +263,7 @@ updatebot:
                         "updatebot": {
                             "maintainer-phab": "tjr",
                             "maintainer-bz": "a@example.com",
+                            "tracking": "commit",
                             "tasks": [
                                 {
                                     "type": "vendoring",
@@ -746,10 +732,7 @@ updatebot:
                             "revision": "v1.6.37",
                             "url": "https://www.cairographics.org/",
                         },
-                        "bugzilla": {
-                            "component": "Graphics",
-                            "product": "Core",
-                        },
+                        "bugzilla": {"component": "Graphics", "product": "Core"},
                     },
                     b"""
 ---
diff --git a/python/mozbuild/mozbuild/vendor/moz_yaml.py b/python/mozbuild/mozbuild/vendor/moz_yaml.py
index 032908c5ff82..55fa3b364c9d 100644
--- a/python/mozbuild/mozbuild/vendor/moz_yaml.py
+++ b/python/mozbuild/mozbuild/vendor/moz_yaml.py
@@ -121,6 +121,10 @@ updatebot:
   # Bugzilla email address for a maintainer of the library, used for needinfos
   maintainer-bz: tom@mozilla.com
 
+  # Type of git reference (commit, tag) to track updates from.
+  # If omitted, will default to tracking commits.
+  tracking: commit
+
   # The tasks that Updatebot can run. Only one of each task is currently permitted
   # optional
   tasks:
@@ -361,15 +365,13 @@ def _schema_1():
             "updatebot": {
                 Required("maintainer-phab"): All(str, Length(min=1)),
                 Required("maintainer-bz"): All(str, Length(min=1)),
+                "tracking": All(str, Length(min=1)),
                 "tasks": All(
                     UpdatebotTasks(),
                     [
                         {
                             Required("type"): In(
-                                [
-                                    "vendoring",
-                                    "commit-alert",
-                                ],
+                                ["vendoring", "commit-alert"],
                                 msg="Invalid type specified in tasks",
                             ),
                             "branch": All(str, Length(min=1)),
@@ -377,11 +379,7 @@ def _schema_1():
                             "cc": Unique([str]),
                             "needinfo": Unique([str]),
                             "filter": In(
-                                [
-                                    "none",
-                                    "security",
-                                    "source-extensions",
-                                ],
+                                ["none", "security", "source-extensions"],
                                 msg="Invalid filter value specified in tasks",
                             ),
                             "source-extensions": Unique([str]),
@@ -460,8 +458,19 @@ def _schema_1_additional(filename, manifest, require_license_file=True):
     if "vendoring" in manifest and "origin" not in manifest:
         raise ValueError('"vendoring" requires an "origin"')
 
-    # If there are Updatebot tasks, then certain fields must be present
+    # If there are Updatebot tasks, then certain fields must be present and
+    # defaults need to be set.
     if "updatebot" in manifest and "tasks" in manifest["updatebot"]:
+        if "tracking" not in manifest["updatebot"]:
+            manifest["updatebot"]["tracking"] = "commit"
+        if (
+            manifest["updatebot"]["tracking"] != "commit"
+            and manifest["updatebot"]["tracking"] != "tag"
+        ):
+            raise ValueError(
+                "Only commit or tag is supported for git references to track, %s was given."
+                % manifest["updatebot"]["tracking"]
+            )
         if "vendoring" not in manifest or "url" not in manifest["vendoring"]:
             raise ValueError(
                 "If Updatebot tasks are specified, a vendoring url must be included."