diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 6cf5ef7..ee9b2a5 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -15,6 +15,9 @@ jobs:
       matrix:
         ruby: ${{ fromJson(needs.ruby-versions.outputs.versions) }}
         os: [ ubuntu-latest, macos-latest ]
+        exclude:
+          - ruby: 2.5
+            os: macos-latest
     runs-on: ${{ matrix.os }}
     steps:
     - uses: actions/checkout@v4
diff --git a/lib/uri/common.rb b/lib/uri/common.rb
index faf75f0..a2b5a8a 100644
--- a/lib/uri/common.rb
+++ b/lib/uri/common.rb
@@ -19,6 +19,8 @@ module URI
   Parser = RFC2396_Parser
   RFC3986_PARSER = RFC3986_Parser.new
   Ractor.make_shareable(RFC3986_PARSER) if defined?(Ractor)
+  RFC2396_PARSER = RFC2396_Parser.new
+  Ractor.make_shareable(RFC2396_PARSER) if defined?(Ractor)
 
   # URI::Parser.new
   DEFAULT_PARSER = Parser.new