diff --git a/Dockerfile b/Dockerfile
index f569dbea906..7c0e81afbc0 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -13,3 +13,5 @@ ADD Gemfile.lock /mastodon/Gemfile.lock
 RUN bundle install --deployment --without test --without development
 
 ADD . /mastodon
+
+VOLUME ['/mastodon/public/system']
diff --git a/app/helpers/stream_entries_helper.rb b/app/helpers/stream_entries_helper.rb
index 60955a0a7e8..5adb09f7746 100644
--- a/app/helpers/stream_entries_helper.rb
+++ b/app/helpers/stream_entries_helper.rb
@@ -25,7 +25,7 @@ module StreamEntriesHelper
     status.mentions.each { |m| mention_hash[m.acct] = m }
     coder = HTMLEntities.new
 
-    auto_link(coder.encode(status.text), link: :urls, html: { target: '_blank', rel: 'nofollow' }).gsub(Account::MENTION_RE) do |m|
+    auto_link(coder.encode(status.text), link: :urls, html: { rel: 'nofollow noopener' }).gsub(Account::MENTION_RE) do |m|
       account = mention_hash[Account::MENTION_RE.match(m)[1]]
       "#{m.split('@').first}<a href=\"#{url_for_target(account)}\" class=\"mention\">@<span>#{account.acct}</span></a>"
     end.html_safe
diff --git a/app/models/account.rb b/app/models/account.rb
index 7577d7bd87e..b3917e6e816 100644
--- a/app/models/account.rb
+++ b/app/models/account.rb
@@ -12,6 +12,10 @@ class Account < ActiveRecord::Base
   has_attached_file :header, styles: { medium: '700x335#' }
   validates_attachment_content_type :header, content_type: /\Aimage\/.*\Z/
 
+  # Local user profile validations
+  validates :display_name, length: { maximum: 30 }, if: 'local?'
+  validates :note, length: { maximum: 124 }, if: 'local?'
+
   # Timelines
   has_many :stream_entries, inverse_of: :account
   has_many :statuses, inverse_of: :account