docs: add how to pass unescaped content

docs/tutorials/jinja_support.rst

@@ -116,6 +116,35 @@ Please see `Jinja documentation <https://jinja.palletsprojects.com/>`_
 for more.
 
 
+Pass Unescaped Content
+----------------------
+
+In case you need to include parts that should not be processed by 
+Jinja, you may pass them using `markupsafe.Markup <https://markupsafe.palletsprojects.com/en/2.1.x/escaping/#markupsafe.Markup>`_:
+
+.. code-block:: python
+
+    from markupsafe import Markup
+
+    email.send(
+        subject='email subject',
+        receivers=['first.last@example.com'],
+        html="""
+            <h1>Hi,</h1>
+            <p>{{ raw_content }}</p>
+            <p>Kind regards
+            <br>{{ sender.full_name }}</p>
+        """,
+        body_params={
+            'raw_content': Markup("<strong>this text is passed unescaped as is</strong>")
+        }
+    )
+
+.. warning::
+
+    For HTML, content only from trusted sources should be left unescaped.
+
+
 Disabling Jinja
 ---------------
 
@@ -128,15 +157,20 @@ to render the bodies, you may also disable it:
         subject='email subject',
         receivers=['first.last@example.com'],
         text="""
-        Hi,
-        {{ these brackets are not processed }}
+            Hi,
+            {{ these brackets are not processed }}
         """,
         html="""
-        <h1>Hi!</h1>
-        <p>
-            {{ these brackets are not processed }}
-        </p>
+            <h1>Hi!</h1>
+            <p>
+                {{ these brackets are not processed }}
+            </p>
         """,
         use_jinja=False
     )
 
+You may also disable Jinja for all sent emails without passing the argument:
+
+.. code-block:: python
+
+    email.use_jinja = False