diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 35a4aa6..848367a 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -15,7 +15,7 @@ jobs:
       matrix:
         os: [ubuntu]
         # We still kind of support Ruby 1.8.7
-        ruby: [2.7, "3.0", 3.1, head, jruby]
+        ruby: ["2.7", "3.0", "3.1", "3.2", "3.3", "head", "jruby"]
 
     name: >-
       ${{matrix.os}}:ruby-${{matrix.ruby}}
@@ -24,7 +24,7 @@ jobs:
 
     steps:
       - name: Check out
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: Set up ruby and bundle
         uses: ruby/setup-ruby@v1
diff --git a/test/helper.rb b/test/helper.rb
index 6b463ad..1e1a514 100644
--- a/test/helper.rb
+++ b/test/helper.rb
@@ -50,6 +50,6 @@ def test_file(filename)
 
 def sleep_until(time)
   if (s = time - Time.now) > 0
-    sleep s
+    sleep s + 0.01
   end
 end
diff --git a/test/test_http_cookie_jar.rb b/test/test_http_cookie_jar.rb
index 969ee7f..e59c018 100644
--- a/test/test_http_cookie_jar.rb
+++ b/test/test_http_cookie_jar.rb
@@ -10,10 +10,8 @@ def test_nonexistent_store
     end
 
     def test_nonexistent_store_in_config
-      assert_raise_with_message(
-        ArgumentError,
-        /cookie store unavailable: :nonexistent, error: cannot load .*nonexistent_store/
-      ) {
+      expected = /cookie store unavailable: :nonexistent, error: (cannot load|no such file to load) .*nonexistent_store/
+      assert_raise_with_message(ArgumentError, expected) {
         HTTP::CookieJar.new(store: :nonexistent)
       }
     end