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@@ -773,6 +773,11 @@ <h2>
         of the user to make or receive calls and use network services,
         including the emergency call service.
       </p>
+      <p>
+        Implementations MAY ignore requests for screen wake lock if, for
+        example, the battery capacity is low, or the user has put their device
+        in a power-saving mode.
+      </p>
       <p>
         It is RECOMMENDED that a user agent provide some UI or indicator that
         allows the user to know when a screen wake lock is active. Providing