--- a/taskcluster/comm_taskgraph/manifests/release_checksums.yml
+++ b/taskcluster/comm_taskgraph/manifests/release_checksums.yml
@@ -1,12 +1,12 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
-
+---
 s3_bucket_paths:
     by-platform:
         thunderbird-release:
             - pub/thunderbird/candidates
 default_locales:  # if given an empty locale, use these locales
     - en-US
 tasktype_map:  # Map task reference to task type.
     release-generate-checksums: build

--- a/taskcluster/comm_taskgraph/manifests/source_checksums.yml
+++ b/taskcluster/comm_taskgraph/manifests/source_checksums.yml
@@ -1,12 +1,12 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
-
+---
 s3_bucket_paths:
     by-platform:
         thunderbird-source:
             - pub/thunderbird/candidates
 default_locales:  # if given an empty locale, use these locales
     - en-US
 tasktype_map:  # Map task reference to task type.
     release-source-checksums-signing: signing

--- a/taskcluster/comm_taskgraph/manifests/source_files.yml
+++ b/taskcluster/comm_taskgraph/manifests/source_files.yml
@@ -1,12 +1,12 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
-
+---
 s3_bucket_paths:
     by-platform:
         thunderbird-source:
             - pub/thunderbird/candidates
 default_locales:  # if given an empty locale, use these locales
     - en-US
 tasktype_map:  # Map task reference to task type.
     release-source-signing: signing

--- a/taskcluster/comm_taskgraph/manifests/thunderbird_candidates.yml
+++ b/taskcluster/comm_taskgraph/manifests/thunderbird_candidates.yml
@@ -1,12 +1,12 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
-
+---
 # This file contains exhaustive information about all the release artifacs that
 # are needed within a type of release.
 #
 # Structure
 # --------
 # `s3_bucket_paths`       -- prefix to be used per product to correctly access our S3 buckets
 # `default_locales`       -- list of locales to be used when composing upstream artifacts or the list of
 #                      destinations. If given an empty locale, it uses these locales instead.

--- a/taskcluster/comm_taskgraph/manifests/thunderbird_candidates_checksums.yml
+++ b/taskcluster/comm_taskgraph/manifests/thunderbird_candidates_checksums.yml
@@ -1,12 +1,12 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
-
+---
 # This file contains exhaustive information about all the release artifacs that
 # are needed within a type of release.
 #
 # Structure
 # --------
 # `s3_bucket_paths`       -- prefix to be used per product to correctly access our S3 buckets
 # `default_locales`       -- list of locales to be used when composing upstream artifacts or the list of
 #                      destinations. If given an empty locale, it uses these locales instead.

--- a/taskcluster/comm_taskgraph/manifests/thunderbird_nightly.yml
+++ b/taskcluster/comm_taskgraph/manifests/thunderbird_nightly.yml
@@ -1,12 +1,12 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
-
+---
 # This file contains exhaustive information about all the release artifacs that
 # are needed within a type of release.
 #
 # Structure
 # --------
 # `s3_bucket_paths`       -- prefix to be used per product to correctly access our S3 buckets
 # `default_locales`       -- list of locales to be used when composing upstream artifacts or the list of
 #                      destinations. If given an empty locale, it uses these locales instead.

--- a/taskcluster/comm_taskgraph/manifests/thunderbird_nightly_checksums.yml
+++ b/taskcluster/comm_taskgraph/manifests/thunderbird_nightly_checksums.yml
@@ -1,12 +1,12 @@
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
-
+---
 s3_bucket_paths:
     - pub/thunderbird/nightly
 default_locales:  # if given an empty locale, use these locales
     - en-US
 tasktype_map:  # Map task reference to task type.
     checksums-signing: signing
 platform_names:
     filename_platform: