diff --git a/.github/workflows/ci_sh_def.yml b/.github/workflows/ci_sh_def.yml
index 1fa7ddefbc..277a8ea63c 100644
--- a/.github/workflows/ci_sh_def.yml
+++ b/.github/workflows/ci_sh_def.yml
@@ -824,7 +824,7 @@ jobs:
       uses: jwlawson/actions-setup-cmake@v1.14
 
     - name: Prepare MSVC
-      uses: ilammy/msvc-dev-cmd@v1.12.1
+      uses: ilammy/msvc-dev-cmd@v1.13.0
       with:
         arch: x86
 
@@ -878,7 +878,7 @@ jobs:
       uses: jwlawson/actions-setup-cmake@v1.14
 
     - name: Prepare MSVC
-      uses: ilammy/msvc-dev-cmd@v1.12.1
+      uses: ilammy/msvc-dev-cmd@v1.13.0
       with:
         arch: x86
 
@@ -987,7 +987,6 @@ jobs:
           mingw-w64-${{matrix.env}}-gcc
           mingw-w64-${{matrix.env}}-python-pip
           mingw-w64-${{matrix.env}}-python-numpy
-          mingw-w64-${{matrix.env}}-python-scipy
           mingw-w64-${{matrix.env}}-cmake
           mingw-w64-${{matrix.env}}-make
           mingw-w64-${{matrix.env}}-python-pytest
@@ -995,6 +994,14 @@ jobs:
           mingw-w64-${{matrix.env}}-boost
           mingw-w64-${{matrix.env}}-catch
 
+    - uses: msys2/setup-msys2@v2
+      if: matrix.sys == 'mingw64'
+      with:
+        msystem: ${{matrix.sys}}
+        install: >-
+          git
+          mingw-w64-${{matrix.env}}-python-scipy
+
     - uses: actions/checkout@v4
 
     - name: Configure C++11
diff --git a/.github/workflows/ci_sh_def.yml.patch b/.github/workflows/ci_sh_def.yml.patch
index fc4378ebf9..a681f8310a 100644
--- a/.github/workflows/ci_sh_def.yml.patch
+++ b/.github/workflows/ci_sh_def.yml.patch
@@ -1,5 +1,5 @@
---- ci.yml	2023-12-14 23:14:57.621249678 -0800
-+++ ci_sh_def.yml	2023-12-14 23:58:28.144667703 -0800
+--- ci.yml	2024-01-16 21:10:28.100295655 -0800
++++ ci_sh_def.yml	2024-01-16 21:10:56.792251785 -0800
 @@ -1,4 +1,16 @@
 -name: CI
 +# PLEASE KEEP THIS GROUP OF FILES IN SYNC AT ALL TIMES:
@@ -165,7 +165,7 @@
          "-DPYBIND11_TEST_OVERRIDE=test_call_policies.cpp;test_gil_scoped.cpp;test_thread.cpp"
  
      - name: Build C++20 - Exercise cmake -DPYBIND11_TEST_OVERRIDE
-@@ -976,6 +1003,7 @@
+@@ -983,6 +1010,7 @@
        run: >-
          cmake -G "MinGW Makefiles" -DCMAKE_CXX_STANDARD=11 -DPYBIND11_WERROR=ON -DDOWNLOAD_CATCH=ON
          -DPYTHON_EXECUTABLE=$(python -c "import sys; print(sys.executable)")
@@ -173,7 +173,7 @@
          -S . -B build
  
      - name: Build C++11
-@@ -997,6 +1025,7 @@
+@@ -1004,6 +1032,7 @@
        run: >-
          cmake -G "MinGW Makefiles" -DCMAKE_CXX_STANDARD=14 -DPYBIND11_WERROR=ON -DDOWNLOAD_CATCH=ON
          -DPYTHON_EXECUTABLE=$(python -c "import sys; print(sys.executable)")
@@ -181,7 +181,7 @@
          -S . -B build2
  
      - name: Build C++14
-@@ -1018,6 +1047,7 @@
+@@ -1025,6 +1054,7 @@
        run: >-
          cmake -G "MinGW Makefiles" -DCMAKE_CXX_STANDARD=17 -DPYBIND11_WERROR=ON -DDOWNLOAD_CATCH=ON
          -DPYTHON_EXECUTABLE=$(python -c "import sys; print(sys.executable)")
@@ -189,7 +189,7 @@
          -S . -B build3
  
      - name: Build C++17
-@@ -1085,6 +1115,7 @@
+@@ -1092,6 +1122,7 @@
            -DDOWNLOAD_EIGEN=ON
            -DCMAKE_CXX_COMPILER=clang++
            -DCMAKE_CXX_STANDARD=17
@@ -197,7 +197,7 @@
  
        - name: Build
          run: cmake --build . -j 2
-@@ -1150,6 +1181,7 @@
+@@ -1157,6 +1188,7 @@
            -DDOWNLOAD_EIGEN=ON
            -DCMAKE_CXX_COMPILER=clang++
            -DCMAKE_CXX_STANDARD=17
@@ -205,7 +205,7 @@
            -DPYTHON_EXECUTABLE=$(python3 -c "import sys; print(sys.executable)")
  
        - name: Build
-@@ -1173,6 +1205,7 @@
+@@ -1180,6 +1212,7 @@
            -DDOWNLOAD_EIGEN=ON
            -DCMAKE_CXX_COMPILER=clang++
            -DCMAKE_CXX_STANDARD=17