diff --git a/.github/workflows/ci-syntax-tests.yml b/.github/workflows/ci-syntax-tests.yml
index 463729a..6a9a041 100644
--- a/.github/workflows/ci-syntax-tests.yml
+++ b/.github/workflows/ci-syntax-tests.yml
@@ -35,21 +35,22 @@ jobs:
             default_packages: master
     steps:
       - name: Checkout Default Packages
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           repository: sublimehq/Packages
           ref: ${{ matrix.default_packages }}
           path: st_syntax_tests/Data/Packages
 
       - name: Delete default package tests
-        run: |-
+        run: |
           find st_syntax_tests/Data/Packages/*/ -type f -name 'syntax_test*' -exec rm -v '{}' \;
 
       - name: Prepare dummy syntaxes
-        run: |-
+        run: |
           packages=st_syntax_tests/Data/Packages
           scopes=(
               source.less
+              source.postcss
               source.sass
               source.scss
               source.stylus
@@ -67,12 +68,12 @@ jobs:
           done
 
       - name: Checkout Astro
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           path: st_syntax_tests/Data/Packages/Astro
 
       - name: Run Syntax Tests for Sublime Text ${{ matrix.build }}
-        run: |-
+        run: |
           if [[ "${{ matrix.build }}" == "latest" ]]; then
             wget -O st_syntax_tests.tar.xz https://download.sublimetext.com/latest/dev/linux/x64/syntax_tests
           else