diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 907d0112..7fe862e1 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -10,7 +10,7 @@ jobs:
     strategy:
       fail-fast: true
       matrix:
-        php: [5.4, 5.5, 5.6, 7.0, 7.1, 7.2, 7.3, 7.4]
+        php: [5.4, 5.5, 5.6, 7.0, 7.1, 7.2, 7.3, 7.4, 8.0]
 
     name: PHP ${{ matrix.php }}
 
diff --git a/composer.json b/composer.json
index 0ff86b5d..5f62d889 100644
--- a/composer.json
+++ b/composer.json
@@ -15,9 +15,6 @@
     "require": {
         "php": ">=5.2"
     },
-    "require-dev": {
-        "simpletest/simpletest": "dev-master#72de02a7b80c6bb8864ef9bf66d41d2f58f826bd"
-    },
     "autoload": {
         "psr-0": { "HTMLPurifier": "library/" },
         "files": ["library/HTMLPurifier.composer.php"],