DOCS-14815 5.1 setWindowFields restriction updates

Author: ianf-mongodb

source/includes/fact-5.1-setWindowFields-snapshot-restriction.rst

@@ -0,0 +1,3 @@
+Starting in MongoDB 5.1 (and 5.0.4), the :pipeline:`$setWindowFields` 
+stage cannot be used within :doc:`transactions </core/transactions>`
+or with :readconcern:`snapshot` read concern.

source/reference/operator/aggregation/setWindowFields.txt

@@ -242,6 +242,12 @@ Restrictions
 
 Restrictions for the :pipeline:`$setWindowFields` stage:
 
+- Starting in MongoDB 5.1 (and 5.0.4), the :pipeline:`$setWindowFields` 
+  stage cannot be used:
+
+  - Within :doc:`transactions </core/transactions>`.
+  - With :readconcern:`snapshot` read concern.
+
 - :ref:`sortBy <setWindowFields-sortBy>` is required for:
 
   - :ref:`Rank <setWindowFields-rank-operators>` and :ref:`order

source/release-notes/5.1-compatibility.txt

@@ -35,6 +35,11 @@ Removed Parameters
 Aggregation
 -----------
 
+``$setWindowFields`` Transactions and Snapshot Read Concern
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. include:: /includes/fact-5.1-setWindowFields-snapshot-restriction.rst
+
 Removed Index Types
 -------------------