diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 2fa4303d9b..03c9225c12 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -100,7 +100,7 @@ jobs:
       run: >
         cmake -S . -B .
         -DPYBIND11_WERROR=ON
-        -DDOWNLOAD_CATCH=OFF
+        -DDOWNLOAD_CATCH=ON
         -DDOWNLOAD_EIGEN=ON
         -DCMAKE_CXX_STANDARD=11
         ${{ matrix.args }}
@@ -111,10 +111,10 @@ jobs:
     - name: Python tests C++11
       run: cmake --build . --target pytest -j 2
 
-    #- name: C++11 tests
-    #  # TODO: Figure out how to load the DLL on Python 3.8+
-    #  if: "!(runner.os == 'Windows' && (matrix.python == 3.8 || matrix.python == 3.9 || matrix.python == '3.10-dev'))"
-    #  run: cmake --build .  --target cpptest -j 2
+    - name: C++11 tests
+      # TODO: Figure out how to load the DLL on Python 3.8+
+      if: "!(runner.os == 'Windows' && (matrix.python == 3.8 || matrix.python == 3.9 || matrix.python == '3.10-dev'))"
+      run: cmake --build .  --target cpptest -j 2
 
     - name: Interface test C++11
       run: cmake --build . --target test_cmake_build
@@ -127,7 +127,7 @@ jobs:
       run: >
         cmake -S . -B build2
         -DPYBIND11_WERROR=ON
-        -DDOWNLOAD_CATCH=OFF
+        -DDOWNLOAD_CATCH=ON
         -DDOWNLOAD_EIGEN=ON
         -DCMAKE_CXX_STANDARD=17
         ${{ matrix.args }}
@@ -139,10 +139,10 @@ jobs:
     - name: Python tests
       run: cmake --build build2 --target pytest
 
-    #- name: C++ tests
-    #  # TODO: Figure out how to load the DLL on Python 3.8+
-    #  if: "!(runner.os == 'Windows' && (matrix.python == 3.8 || matrix.python == 3.9 || matrix.python == '3.10-dev'))"
-    #  run: cmake --build build2 --target cpptest
+    - name: C++ tests
+      # TODO: Figure out how to load the DLL on Python 3.8+
+      if: "!(runner.os == 'Windows' && (matrix.python == 3.8 || matrix.python == 3.9 || matrix.python == '3.10-dev'))"
+      run: cmake --build build2 --target cpptest
 
     - name: Interface test
       run: cmake --build build2 --target test_cmake_build
@@ -754,7 +754,7 @@ jobs:
         cmake -S . -B build
         -G "Visual Studio 16 2019" -A Win32
         -DPYBIND11_WERROR=ON
-        -DDOWNLOAD_CATCH=OFF
+        -DDOWNLOAD_CATCH=ON
         -DDOWNLOAD_EIGEN=ON
         ${{ matrix.args }}
     - name: Build C++11
@@ -800,7 +800,7 @@ jobs:
         cmake -S . -B build
         -G "Visual Studio 14 2015" -A x64
         -DPYBIND11_WERROR=ON
-        -DDOWNLOAD_CATCH=OFF
+        -DDOWNLOAD_CATCH=ON
         -DDOWNLOAD_EIGEN=ON
 
     - name: Build C++14
@@ -849,7 +849,7 @@ jobs:
         cmake -S . -B build
         -G "Visual Studio 15 2017" -A x64
         -DPYBIND11_WERROR=ON
-        -DDOWNLOAD_CATCH=OFF
+        -DDOWNLOAD_CATCH=ON
         -DDOWNLOAD_EIGEN=ON
         -DCMAKE_CXX_STANDARD=${{ matrix.std }}
         ${{ matrix.args }}
diff --git a/CMakeLists.txt b/CMakeLists.txt
index c988ea0b50..68cabadf91 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -105,6 +105,7 @@ set(PYBIND11_HEADERS
     include/pybind11/detail/descr.h
     include/pybind11/detail/init.h
     include/pybind11/detail/internals.h
+    include/pybind11/detail/pragma_warning_block.h
     include/pybind11/detail/type_caster_base.h
     include/pybind11/detail/typeid.h
     include/pybind11/attr.h
diff --git a/include/pybind11/detail/pragma_warning_block.h b/include/pybind11/detail/pragma_warning_block.h
new file mode 100644
index 0000000000..e8ce12bf38
--- /dev/null
+++ b/include/pybind11/detail/pragma_warning_block.h
@@ -0,0 +1,33 @@
+#pragma once
+
+#if defined(__INTEL_COMPILER)
+#  pragma warning push
+#  pragma warning disable 68    // integer conversion resulted in a change of sign
+#  pragma warning disable 186   // pointless comparison of unsigned integer with zero
+#  pragma warning disable 878   // incompatible exception specifications
+#  pragma warning disable 1334  // the "template" keyword used for syntactic disambiguation may only be used within a template
+#  pragma warning disable 1682  // implicit conversion of a 64-bit integral type to a smaller integral type (potential portability problem)
+#  pragma warning disable 1786  // function "strdup" was declared deprecated
+#  pragma warning disable 1875  // offsetof applied to non-POD (Plain Old Data) types is nonstandard
+#  pragma warning disable 2196  // warning #2196: routine is both "inline" and "noinline"
+#elif defined(_MSC_VER)
+#  pragma warning(push)
+#  pragma warning(disable: 4100) // warning C4100: Unreferenced formal parameter
+#  pragma warning(disable: 4127) // warning C4127: Conditional expression is constant
+#  pragma warning(disable: 4512) // warning C4512: Assignment operator was implicitly defined as deleted
+#  pragma warning(disable: 4800) // warning C4800: 'int': forcing value to bool 'true' or 'false' (performance warning)
+#  pragma warning(disable: 4996) // warning C4996: The POSIX name for this item is deprecated. Instead, use the ISO C and C++ conformant name
+#  pragma warning(disable: 4702) // warning C4702: unreachable code
+#  pragma warning(disable: 4522) // warning C4522: multiple assignment operators specified
+#  pragma warning(disable: 4505) // warning C4505: 'PySlice_GetIndicesEx': unreferenced local function has been removed (PyPy only)
+#elif defined(__GNUG__) && !defined(__clang__)
+#  pragma GCC diagnostic push
+#  pragma GCC diagnostic ignored "-Wunused-but-set-parameter"
+#  pragma GCC diagnostic ignored "-Wunused-but-set-variable"
+#  pragma GCC diagnostic ignored "-Wmissing-field-initializers"
+#  pragma GCC diagnostic ignored "-Wstrict-aliasing"
+#  pragma GCC diagnostic ignored "-Wattributes"
+#  if __GNUC__ >= 7
+#    pragma GCC diagnostic ignored "-Wnoexcept-type"
+#  endif
+#endif
diff --git a/include/pybind11/pybind11.h b/include/pybind11/pybind11.h
index 616fa70255..c289966cc5 100644
--- a/include/pybind11/pybind11.h
+++ b/include/pybind11/pybind11.h
@@ -10,37 +10,9 @@
 
 #pragma once
 
-#if defined(__INTEL_COMPILER)
-#  pragma warning push
-#  pragma warning disable 68    // integer conversion resulted in a change of sign
-#  pragma warning disable 186   // pointless comparison of unsigned integer with zero
-#  pragma warning disable 878   // incompatible exception specifications
-#  pragma warning disable 1334  // the "template" keyword used for syntactic disambiguation may only be used within a template
-#  pragma warning disable 1682  // implicit conversion of a 64-bit integral type to a smaller integral type (potential portability problem)
-#  pragma warning disable 1786  // function "strdup" was declared deprecated
-#  pragma warning disable 1875  // offsetof applied to non-POD (Plain Old Data) types is nonstandard
-#  pragma warning disable 2196  // warning #2196: routine is both "inline" and "noinline"
-#elif defined(_MSC_VER)
-#  pragma warning(push)
-#  pragma warning(disable: 4100) // warning C4100: Unreferenced formal parameter
-#  pragma warning(disable: 4127) // warning C4127: Conditional expression is constant
-#  pragma warning(disable: 4512) // warning C4512: Assignment operator was implicitly defined as deleted
-#  pragma warning(disable: 4800) // warning C4800: 'int': forcing value to bool 'true' or 'false' (performance warning)
-#  pragma warning(disable: 4996) // warning C4996: The POSIX name for this item is deprecated. Instead, use the ISO C and C++ conformant name
-#  pragma warning(disable: 4702) // warning C4702: unreachable code
-#  pragma warning(disable: 4522) // warning C4522: multiple assignment operators specified
-#  pragma warning(disable: 4505) // warning C4505: 'PySlice_GetIndicesEx': unreferenced local function has been removed (PyPy only)
-#elif defined(__GNUG__) && !defined(__clang__)
-#  pragma GCC diagnostic push
-#  pragma GCC diagnostic ignored "-Wunused-but-set-parameter"
-#  pragma GCC diagnostic ignored "-Wunused-but-set-variable"
-#  pragma GCC diagnostic ignored "-Wmissing-field-initializers"
-#  pragma GCC diagnostic ignored "-Wstrict-aliasing"
-#  pragma GCC diagnostic ignored "-Wattributes"
-#  if __GNUC__ >= 7
-#    pragma GCC diagnostic ignored "-Wnoexcept-type"
-#  endif
-#endif
+// Legacy pragma warning block moved to separate file, to enable iwyu cleanup of newly developed
+// code, without having to open up this can of worms. #HelpAppreciated cleaning this up.
+#include "detail/pragma_warning_block.h"
 
 #include "attr.h"
 #include "gil.h"
diff --git a/tests/extra_python_package/test_files.py b/tests/extra_python_package/test_files.py
index c1d12ed76b..1149afead2 100644
--- a/tests/extra_python_package/test_files.py
+++ b/tests/extra_python_package/test_files.py
@@ -42,6 +42,7 @@
     "include/pybind11/detail/descr.h",
     "include/pybind11/detail/init.h",
     "include/pybind11/detail/internals.h",
+    "include/pybind11/detail/pragma_warning_block.h",
     "include/pybind11/detail/type_caster_base.h",
     "include/pybind11/detail/typeid.h",
 }