diff --git a/.github/actions/test_artifacts/action.yml b/.github/actions/test_artifacts/action.yml
index e68fec961b..0afcd6d779 100644
--- a/.github/actions/test_artifacts/action.yml
+++ b/.github/actions/test_artifacts/action.yml
@@ -1,31 +1,41 @@
 name: 'test_artifacts'
 description: "Upload failed test artifacts"
+inputs:
+  artifact-name:
+    description: Name of the artifact
+    required: true
+
 runs:
   using: "composite"
   steps:
-    - name: Collect matrix properties for naming
-      uses: actions/github-script@v8
-      id: matrix-props
-      env:
-        MATRIX_PROPS: ${{ toJSON(matrix) }}
-      with:
-        # An array-flattening-to-string JavaScript function.
-        script: |
-          const f = function (x) { return x.toString().length > 0; }
-          const g = function (x) {
-            return (Array.isArray(x))
-              ? x.filter(f)
-                .map((function (h) { return function (y) { return h(y); }; })(g))
-                .join('-')
-              : x;
-          }
-          return Object.values(JSON.parse(process.env.MATRIX_PROPS))
-            .filter(f)
-            .map(g)
-            .join('-');
-        # By default, the JSON-encoded return value of the function is
-        # set as the "result".
-        result-encoding: string
+# MacVim: We don't use a matrix within the reused
+# workflow, and so would prefer to manually pass
+# in the name of the artifact rather than deriving
+# it from the matrix automatically like in Vim
+# upstream.
+#    - name: Collect matrix properties for naming
+#      uses: actions/github-script@v8
+#      id: matrix-props
+#      env:
+#        MATRIX_PROPS: ${{ toJSON(inputs) }}
+#      with:
+#        # An array-flattening-to-string JavaScript function.
+#        script: |
+#          const f = function (x) { return x.toString().length > 0; }
+#          const g = function (x) {
+#            return (Array.isArray(x))
+#              ? x.filter(f)
+#                .map((function (h) { return function (y) { return h(y); }; })(g))
+#                .join('-')
+#              : x;
+#          }
+#          return Object.values(JSON.parse(process.env.MATRIX_PROPS))
+#            .filter(f)
+#            .map(g)
+#            .join('-');
+#        # By default, the JSON-encoded return value of the function is
+#        # set as the "result".
+#        result-encoding: string
     - name: Upload failed tests
       uses: actions/upload-artifact@v4
       with:
@@ -35,7 +45,7 @@ runs:
           github.run_attempt,
           github.job,
           strategy.job-index,
-          steps.matrix-props.outputs.result) }}
+          inputs.artifact-name) }}
 
         # A file, directory or wildcard pattern that describes what
         # to upload.
diff --git a/.github/actions/test_macvim_artifacts/action.yml b/.github/actions/test_macvim_artifacts/action.yml
index e02eec625e..a0ec557045 100644
--- a/.github/actions/test_macvim_artifacts/action.yml
+++ b/.github/actions/test_macvim_artifacts/action.yml
@@ -1,6 +1,14 @@
 # This is a clone of test_artifacts for MacVim-specific files
+# This should be almost identical to test_artifacts, other than the artifact
+# name/path. In the future we could potentially combine the two, but for now
+# it's simpler to keep them separate to ease upstream merging.
 name: 'test_macvim_artifacts'
 description: "Upload failed MacVim test artifacts"
+inputs:
+  artifact-name:
+    description: Name of the artifact
+    required: true
+
 runs:
   using: "composite"
   steps:
@@ -8,7 +16,12 @@ runs:
       uses: actions/upload-artifact@v4
       with:
         # Name of the artifact to upload.
-        name: ${{ github.workflow }}-${{ github.job }}-${{ join(matrix.*, '-') }}-failed-macvim-tests
+        name: ${{ format('GH-{0}-{1}-{2}-{3}-{4}-failed-macvim-tests',
+          github.run_id,
+          github.run_attempt,
+          github.job,
+          strategy.job-index,
+          inputs.artifact-name) }}
 
         # A file, directory or wildcard pattern that describes what
         # to upload.
diff --git a/.github/workflows/macvim-buildtest.yaml b/.github/workflows/macvim-buildtest.yaml
index 3cd5987636..84104fca32 100644
--- a/.github/workflows/macvim-buildtest.yaml
+++ b/.github/workflows/macvim-buildtest.yaml
@@ -353,6 +353,8 @@ jobs:
       - name: Upload failed MacVim test results
         if: ${{ !cancelled() && failure() && steps.test_macvim.conclusion == 'failure' }}
         uses: ./.github/actions/test_macvim_artifacts
+        with:
+          artifact-name: ${{ format('{0}-{1}', inputs.os, inputs.xcode) }}
 
       - name: Build Vim test binaries
         run: |
@@ -385,6 +387,8 @@ jobs:
       - name: Upload failed test files
         if: ${{ !cancelled() && failure() }}
         uses: ./.github/actions/test_artifacts
+        with:
+          artifact-name: ${{ format('{0}-{1}', inputs.os, inputs.xcode) }}
 
       - name: Build MacVim dmg image
         if: inputs.publish && (startsWith(github.ref, 'refs/tags/') || github.ref == 'refs/heads/master')