diff --git a/.github/workflows/linux.yml b/.github/workflows/linux.yml
index 520eff89dbb..a0adbed7f0e 100644
--- a/.github/workflows/linux.yml
+++ b/.github/workflows/linux.yml
@@ -100,7 +100,11 @@ jobs:
         run: ./mach test-scripts
       - name: Unit tests
         if: ${{ inputs.unit-tests || github.ref_name == 'try-linux' }}
-        run: python3 ./mach test-unit ${{ env.cargo_profile_option }}
+        uses: nick-fields/retry@v2
+        with:
+          timeout_minutes: 20
+          max_attempts: 2 # https://github.com/servo/servo/issues/30683
+          command: python ./mach test-unit ${{ env.cargo_profile_option }}
       - name: Rename build timing
         run: cp -r target/cargo-timings target/cargo-timings-linux
       - name: Archive build timing
diff --git a/.github/workflows/mac.yml b/.github/workflows/mac.yml
index 54f80675674..5e22f0bfede 100644
--- a/.github/workflows/mac.yml
+++ b/.github/workflows/mac.yml
@@ -93,8 +93,11 @@ jobs:
         run: ./mach test-scripts
       - name: Unit tests
         if: ${{ inputs.unit-tests || github.ref_name == 'try-mac' }}
-        timeout-minutes: 30 # https://github.com/servo/servo/issues/30275
-        run: python3 ./mach test-unit ${{ env.cargo_profile_option }}
+        uses: nick-fields/retry@v2
+        with:
+          timeout_minutes: 20 # https://github.com/servo/servo/issues/30275
+          max_attempts: 3 # https://github.com/servo/servo/issues/30683
+          command: python3 ./mach test-unit ${{ env.cargo_profile_option }}
       - name: Build mach package
         run: python3 ./mach package ${{ env.cargo_profile_option }}
       - name: Run smoketest for mach package
diff --git a/.github/workflows/windows.yml b/.github/workflows/windows.yml
index 68f84bea2b3..d30129e095e 100644
--- a/.github/workflows/windows.yml
+++ b/.github/workflows/windows.yml
@@ -85,7 +85,11 @@ jobs:
         run: python mach smoketest --angle ${{ env.cargo_profile_option }}
       - name: Unit tests
         if: ${{ inputs.unit-tests || github.ref_name == 'try-windows' }}
-        run: python mach test-unit ${{ env.cargo_profile_option }}
+        uses: nick-fields/retry@v2
+        with:
+          timeout_minutes: 30
+          max_attempts: 3 # https://github.com/servo/servo/issues/30683
+          command: python mach test-unit ${{ env.cargo_profile_option }} -- -- --test-threads=1
       - name: Rename build timing
         run: cp C:\a\servo\servo\target\cargo-timings C:\a\servo\servo\target\cargo-timings-windows -Recurse
       - name: Archive build timing