diff --git a/.github/workflows/rspec.yml b/.github/workflows/rspec.yml
index 52f3fbb..551fe40 100644
--- a/.github/workflows/rspec.yml
+++ b/.github/workflows/rspec.yml
@@ -22,13 +22,17 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: ["3.0", 3.1, 3.2]
-        gemfile: ["6.1", "7.0", "main"]
+        ruby: ["3.0", 3.1, 3.2, 3,3]
+        gemfile: ["6.1", "7.0", "7.1", "main"]
         exclude:
+          - ruby: "3.0"
+            gemfile: "main"
           - ruby: "3.1"
             gemfile: "6.1"
           - ruby: "3.2"
             gemfile: "6.1"
+          - ruby: "3.3"
+            gemfile: "6.1"
     steps:
       - name: Install packages
         run: |
diff --git a/.vscode/settings.json b/.vscode/settings.json
index 2e70ced..bce6ffe 100644
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -1,6 +1,6 @@
 {
   "editor.codeActionsOnSave": {
-    "source.fixAll.eslint": true,
+    "source.fixAll.eslint": "explicit"
   },
   "typescript.tsdk": "node_modules/typescript/lib",
   "typescript.preferences.importModuleSpecifier": "non-relative",
diff --git a/gemfiles/7.1.gemfile b/gemfiles/7.1.gemfile
new file mode 100644
index 0000000..f57276e
--- /dev/null
+++ b/gemfiles/7.1.gemfile
@@ -0,0 +1,5 @@
+source "http://rubygems.org"
+
+gem "rails", "~> 7.1"
+
+gemspec :path => "../"
diff --git a/lib/copy_tuner_client/configuration.rb b/lib/copy_tuner_client/configuration.rb
index d5a13be..f8430a3 100644
--- a/lib/copy_tuner_client/configuration.rb
+++ b/lib/copy_tuner_client/configuration.rb
@@ -157,13 +157,20 @@ def initialize
       self.upload_disabled_environments = %w[production staging]
       self.s3_host = 'copy-tuner-data-prod.s3.amazonaws.com'
       self.disable_copyray_comment_injection = false
-      self.html_escape = false
+      # TODO: 0.18.0以降のバージョンで初期値をtrueにしたい
+      self.html_escape = nil
       self.ignored_keys = []
       self.ignored_key_handler = -> (e) { raise e }
 
       @applied = false
     end
 
+    def html_escape
+      raise 'CopyTunerClient.configuration.html_escape is required' if @html_escape.nil?
+
+      @html_escape
+    end
+
     # Allows config options to be read like a hash
     #
     # @param [Symbol] option Key for a given attribute
diff --git a/lib/copy_tuner_client/version.rb b/lib/copy_tuner_client/version.rb
index c9aed9a..2872753 100644
--- a/lib/copy_tuner_client/version.rb
+++ b/lib/copy_tuner_client/version.rb
@@ -1,6 +1,6 @@
 module CopyTunerClient
   # Client version
-  VERSION = '0.16.3'.freeze
+  VERSION = '0.17.0'.freeze
 
   # API version being used to communicate with the server
   API_VERSION = '2.0'.freeze
diff --git a/spec/copy_tuner_client/i18n_backend_spec.rb b/spec/copy_tuner_client/i18n_backend_spec.rb
index aaa2e1c..06c86ff 100644
--- a/spec/copy_tuner_client/i18n_backend_spec.rb
+++ b/spec/copy_tuner_client/i18n_backend_spec.rb
@@ -111,10 +111,10 @@ def build_backend
     expect(cache['en.test.key']).to eq 'default %{interpolate}'
   end
 
-  it "marks strings as html safe" do
+  it "dose not mark strings as html safe" do
     cache['en.test.key'] = FakeHtmlSafeString.new("Hello")
     backend = build_backend
-    expect(backend.translate('en', 'test.key')).to be_html_safe
+    expect(backend.translate('en', 'test.key')).to_not be_html_safe
   end
 
   it "looks up an array of defaults" do
diff --git a/spec/support/client_spec_helpers.rb b/spec/support/client_spec_helpers.rb
index db6f63e..7794faa 100644
--- a/spec/support/client_spec_helpers.rb
+++ b/spec/support/client_spec_helpers.rb
@@ -4,6 +4,7 @@ def reset_config
     CopyTunerClient.configure(false) do |config|
       config.api_key = 'abc123'
       config.s3_host = 'copy-tuner.com'
+      config.html_escape = true
     end
   end
 end