diff --git a/lib/redmine/plugin_loader.rb b/lib/redmine/plugin_loader.rb
index ea6c4a8b2..be7f914f4 100644
--- a/lib/redmine/plugin_loader.rb
+++ b/lib/redmine/plugin_loader.rb
@@ -88,7 +88,7 @@ module Redmine
 
     # Absolute path to the plublic directory where plugins assets are copied
     cattr_accessor :public_directory
-    self.public_directory = Rails.root.join('public/plugin_assets')
+    self.public_directory = Rails.public_path.join('plugin_assets')
 
     def self.create_assets_reloader
       plugin_assets_dirs = {}
diff --git a/lib/redmine/wiki_formatting/common_mark/helper.rb b/lib/redmine/wiki_formatting/common_mark/helper.rb
index 5d3141c26..244055dbe 100644
--- a/lib/redmine/wiki_formatting/common_mark/helper.rb
+++ b/lib/redmine/wiki_formatting/common_mark/helper.rb
@@ -26,7 +26,7 @@ module Redmine
           help_file = "/help/#{current_language.to_s.downcase}/wiki_syntax_common_mark.html"
           # fall back to the english help page if there is none for the current
           # language
-          unless File.readable? Rails.root.join("public", help_file)
+          unless File.readable? Rails.public_path.join(help_file)
             help_file = "/help/en/wiki_syntax_common_mark.html"
           end
           url = "#{Redmine::Utils.relative_url_root}#{help_file}"