diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 1368b72..5a1c30c 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -13,7 +13,7 @@ jobs:
 
     strategy:
       matrix:
-        python-version: ["3.7", "3.8", "3.9", "3.10"]
+        python-version: ["3.7", "3.8", "3.9", "3.10", "3.11"]
         # TODO: remove `7.1` in the next release
         pytest-version: ["~=6.2", "~=7.1", "~=7.2"]
 
diff --git a/pytest_mypy_plugins/collect.py b/pytest_mypy_plugins/collect.py
index ea1c653..265db91 100644
--- a/pytest_mypy_plugins/collect.py
+++ b/pytest_mypy_plugins/collect.py
@@ -77,7 +77,7 @@ def construct_mapping(self, node: yaml.MappingNode, deep: bool = False) -> Dict[
         mapping = super().construct_mapping(node, deep=deep)
         # Add 1 so line numbering starts at 1
         starting_line = node.start_mark.line + 1
-        for (title_node, contents_node) in node.value:
+        for title_node, contents_node in node.value:
             if title_node.value == "main":
                 starting_line = title_node.start_mark.line + 1
         mapping["__line__"] = starting_line
diff --git a/pytest_mypy_plugins/item.py b/pytest_mypy_plugins/item.py
index 1ffd091..47c714b 100644
--- a/pytest_mypy_plugins/item.py
+++ b/pytest_mypy_plugins/item.py
@@ -107,7 +107,7 @@ def flush_errors(new_messages: List[str], serious: bool) -> None:
         build.build(sources, options, flush_errors=flush_errors, fscache=fscache)
 
     except SystemExit as sysexit:
-        return sysexit.code
+        return sysexit.code if isinstance(sysexit.code, int) else 1
     finally:
         fscache.flush()
 
@@ -241,7 +241,6 @@ def runtest(self) -> None:
             temp_dir = tempfile.TemporaryDirectory(prefix="pytest-mypy-", dir=self.root_directory)
 
         except (FileNotFoundError, PermissionError, NotADirectoryError) as e:
-
             raise TypecheckAssertionError(
                 error_message=f"Testing base directory {self.root_directory} must exist and be writable"
             ) from e
diff --git a/pytest_mypy_plugins/tests/test-parametrized.yml b/pytest_mypy_plugins/tests/test-parametrized.yml
index 4df19e2..3947dda 100644
--- a/pytest_mypy_plugins/tests/test-parametrized.yml
+++ b/pytest_mypy_plugins/tests/test-parametrized.yml
@@ -45,3 +45,5 @@
   out: |
     main:2: note: Revealed type is "{{ rt }}"
     main:4: error: Unsupported operand types for / ("str" and "int")
+  mypy_config: |
+    hide_error_codes = True
diff --git a/pytest_mypy_plugins/tests/test-paths-from-env.yml b/pytest_mypy_plugins/tests/test-paths-from-env.yml
index 62ef522..739cbb1 100644
--- a/pytest_mypy_plugins/tests/test-paths-from-env.yml
+++ b/pytest_mypy_plugins/tests/test-paths-from-env.yml
@@ -11,3 +11,5 @@
       content: |
         def extra_fn() -> None:
             pass
+  mypy_config: |
+    hide_error_codes = True
diff --git a/pytest_mypy_plugins/tests/test-simple-cases.yml b/pytest_mypy_plugins/tests/test-simple-cases.yml
index e324f46..aacc6a8 100644
--- a/pytest_mypy_plugins/tests/test-simple-cases.yml
+++ b/pytest_mypy_plugins/tests/test-simple-cases.yml
@@ -58,6 +58,8 @@
   main: |
     a = 1
     a.lower()  # E: "int" has no attribute "lower"
+  mypy_config: |
+    hide_error_codes = True
 
 
 - case: custom_mypy_config_strict_optional_true_set
@@ -88,6 +90,8 @@
   main: |
     a = 1
     a.lower()  # E: "int" has no attribute "lower"
+  mypy_config: |
+    hide_error_codes = True
 
 - case: fail_if_message_does_not_match
   expect_fail: yes
@@ -101,4 +105,4 @@
     a = 'abc'
     reveal_type(a)
   out: |
-    main:2: note: Some other message
\ No newline at end of file
+    main:2: note: Some other message
diff --git a/pytest_mypy_plugins/tests/test_parametrized_html_escape.yml b/pytest_mypy_plugins/tests/test_parametrized_html_escape.yml
new file mode 100644
index 0000000..3d0e2a1
--- /dev/null
+++ b/pytest_mypy_plugins/tests/test_parametrized_html_escape.yml
@@ -0,0 +1,11 @@
+- case: gt_in_rt
+  parametrized:
+    - val: bool
+      rt: def (builtins.object =) -> builtins.bool
+  main: |
+    reveal_type({{ val }})  # N: Revealed type is "{{ rt }}"
+
+
+- case: gt_in_comment
+  main: |
+    reveal_type(bool)  # N: Revealed type is "def (builtins.object =) -> builtins.bool"
diff --git a/pytest_mypy_plugins/utils.py b/pytest_mypy_plugins/utils.py
index 837b3d7..2844ce0 100644
--- a/pytest_mypy_plugins/utils.py
+++ b/pytest_mypy_plugins/utils.py
@@ -1,6 +1,7 @@
 # Borrowed from Pew.
 # See https://github.com/berdario/pew/blob/master/pew/_utils.py#L82
 import contextlib
+import html
 import inspect
 import io
 import os
@@ -352,7 +353,9 @@ def extract_output_matchers_from_out(out: str, params: Mapping[str, Any], regex:
 
 
 def render_template(template: str, data: Mapping[str, Any]) -> str:
-    return chevron.render(template=template, data={k: v if v is not None else "None" for k, v in data.items()})
+    return html.unescape(
+        chevron.render(template=template, data={k: v if v is not None else "None" for k, v in data.items()})
+    )
 
 
 def get_func_first_lnum(attr: Callable[..., None]) -> Optional[Tuple[int, List[str]]]:
diff --git a/setup.py b/setup.py
index 0d59571..2175fd4 100644
--- a/setup.py
+++ b/setup.py
@@ -39,6 +39,7 @@
         "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
+        "Programming Language :: Python :: 3.11",
         "Typing :: Typed",
     ],
 )