diff --git a/app/helpers/formatting_helper.rb b/app/helpers/formatting_helper.rb
index 3715fc27d..a10ca17fa 100644
--- a/app/helpers/formatting_helper.rb
+++ b/app/helpers/formatting_helper.rb
@@ -23,7 +23,7 @@ module FormattingHelper
       status.text,
       status.local?,
       preloaded_accounts: [status.account] + (status.respond_to?(:active_mentions) ? status.active_mentions.map(&:account) : []),
-      quote: status.respond_to?(:quote) && status.quote
+      quote: status.respond_to?(:quote) && status.quote,
     )
   end
 
diff --git a/app/lib/activitypub/activity/create.rb b/app/lib/activitypub/activity/create.rb
index b96b1289e..b8e3605bf 100644
--- a/app/lib/activitypub/activity/create.rb
+++ b/app/lib/activitypub/activity/create.rb
@@ -434,8 +434,14 @@ class ActivityPub::Activity::Create < ActivityPub::Activity
   end
 
   def process_quote
-    return unless (@quote = quote_from_url(@object['quoteUrl']))
-
+    if @object.key?('quoteUrl')
+      url = @object['quoteUrl']
+    elsif @object.key?('quoteURL')
+      url = @object['quoteURL']
+    elsif @object.key?('_misskey_quote')
+      url = @object['_misskey_quote']
+    end
+    return unless (@quote = quote_from_url(url))
     %r{<br><br>RE:\s</span><a.*</a>}.match(@object['content']) do |m|
       @object['content'] = @object['content'].sub(m[0], "</span><span class=\"quote-inline\">#{m[0].sub(%r{</span>}, '')}</span>")
     end
diff --git a/app/lib/activitypub/case_transform.rb b/app/lib/activitypub/case_transform.rb
index bf5de7221..fae59bd53 100644
--- a/app/lib/activitypub/case_transform.rb
+++ b/app/lib/activitypub/case_transform.rb
@@ -2,6 +2,11 @@
 
 module ActivityPub::CaseTransform
   class << self
+    NO_CONVERT_VALUES = %w(
+      _misskey_content
+      _misskey_quote
+    ).freeze
+
     def camel_lower_cache
       @camel_lower_cache ||= {}
     end
@@ -12,7 +17,9 @@ module ActivityPub::CaseTransform
       when Hash then value.deep_transform_keys! { |key| camel_lower(key) }
       when Symbol then camel_lower(value.to_s).to_sym
       when String
-        camel_lower_cache[value] ||= if value.start_with?('_:')
+        camel_lower_cache[value] ||= if NO_CONVERT_VALUES.include?(value)
+                                       value
+                                     elsif value.start_with?('_:')
                                        "_:#{value.delete_prefix('_:').underscore.camelize(:lower)}"
                                      elsif LanguagesHelper::ISO_639_1_REGIONAL.key?(value.to_sym)
                                        value