diff --git a/.github/workflows/Downgrade.yml b/.github/workflows/Downgrade.yml
index b154c484..e34fb072 100644
--- a/.github/workflows/Downgrade.yml
+++ b/.github/workflows/Downgrade.yml
@@ -42,14 +42,16 @@ jobs:
         with:
           skip: LinearAlgebra
           projects: ., test
-      - uses: julia-actions/julia-buildpkg@v1
-        env:
-          PYTHON: ""
-      - name: Run tests without coverage
-        uses: julia-actions/julia-runtest@v1
-        with:
-          coverage: false
-          allow_reresolve: false
-          force_latest_compatible_version: false
-        env:
-          PYTHON: ""
+          mode: forcedeps
+      # We run the tests manually instead of using julia-action/julia-builpkg and julia-action/julia-runtest or `Pkg.test`
+      # because otherwise the downgraded Manifest.toml is not used in the tests under julia <v1.12
+      # see also https://github.com/julia-actions/julia-downgrade-compat/blob/00f940b7be2b50389571ed016d603be561649103/README.md#L89
+      - name: Run tests
+        run: |
+          julia --project=test --color=yes -e '
+            import Pkg
+            Pkg.develop(Pkg.PackageSpec(path=pwd()))
+            Pkg.instantiate()
+            Pkg.status(; mode = Pkg.PKGMODE_MANIFEST)
+            include("test/runtests.jl")
+          '
diff --git a/test/Project.toml b/test/Project.toml
index 49935b22..c72bc77a 100644
--- a/test/Project.toml
+++ b/test/Project.toml
@@ -20,7 +20,7 @@ ExplicitImports = "1.6.0"
 LinearAlgebra = "1"
 Meshes = "0.53, 0.54, 0.55, 0.56"
 SpecialFunctions = "2"
-StaticArrays = "1"
+StaticArrays = "1.9.8"
 TestItemRunner = "1"
 TestItems = "1"
 Unitful = "1.19"