diff --git a/.github/workflows/test-unit.yml b/.github/workflows/test-unit.yml
index 9fa1778ee..9f60c7885 100644
--- a/.github/workflows/test-unit.yml
+++ b/.github/workflows/test-unit.yml
@@ -56,10 +56,10 @@ jobs:
         if [ $(php -r 'printf(version_compare(PHP_VERSION, "7.0.0", ">=") ? 1 : 0);') = '1' ]
         then
           pecl install xdebug
-          docker-php-ext-enable xdebug
         else
-          echo "Not applicable; PHP version $(php -r 'printf(PHP_VERSION);') is too old"
+          pecl install xdebug-2.5.5
         fi
+        docker-php-ext-enable xdebug
 
     - name: Install PHP pdo_mysql extension
       run: docker-php-ext-install pdo_mysql