diff --git a/README.md b/README.md
index 0eb9bbe3e..3add10473 100644
--- a/README.md
+++ b/README.md
@@ -52,7 +52,6 @@ If you would like, you can [support the development of this project on Patreon][
 
 - `LOCAL_DOMAIN` should be the domain/hostname of your instance. This is **absolutely required** as it is used for generating unique IDs for everything federation-related
 - `LOCAL_HTTPS` set it to `true` if HTTPS works on your website. This is used to generate canonical URLs, which is also important when generating and parsing federation-related IDs
-- `HUB_URL` should be the URL of the PubsubHubbub service that your instance is going to use. By default it is the open service of Superfeedr
 
 Consult the example configuration file, `.env.production.sample` for the full list. Among other things you need to set details for the SMTP server you are going to use.
 
diff --git a/app/models/tag.rb b/app/models/tag.rb
index e5b0511ae..77a73cce8 100644
--- a/app/models/tag.rb
+++ b/app/models/tag.rb
@@ -3,7 +3,7 @@
 class Tag < ApplicationRecord
   has_and_belongs_to_many :statuses
 
-  HASHTAG_RE = /(?:^|[^\/\w])#([[:word:]_]+)/i
+  HASHTAG_RE = /(?:^|[^\/\w])#([[:word:]_]*[[:alpha:]_][[:word:]_]*)/i
 
   validates :name, presence: true, uniqueness: true
 
diff --git a/app/services/favourite_service.rb b/app/services/favourite_service.rb
index 2f280e03f..5c04cfee4 100644
--- a/app/services/favourite_service.rb
+++ b/app/services/favourite_service.rb
@@ -8,7 +8,6 @@ class FavouriteService < BaseService
   def call(account, status)
     favourite = Favourite.create!(account: account, status: status)
 
-    HubPingWorker.perform_async(account.id)
     Pubsubhubbub::DistributionWorker.perform_async(favourite.stream_entry.id)
 
     if status.local?
diff --git a/app/services/follow_service.rb b/app/services/follow_service.rb
index 423b833cf..ed9b62455 100644
--- a/app/services/follow_service.rb
+++ b/app/services/follow_service.rb
@@ -20,7 +20,6 @@ class FollowService < BaseService
 
     merge_into_timeline(target_account, source_account)
 
-    HubPingWorker.perform_async(source_account.id)
     Pubsubhubbub::DistributionWorker.perform_async(follow.stream_entry.id)
 
     follow
diff --git a/app/services/post_status_service.rb b/app/services/post_status_service.rb
index 9e0ced129..d5204151b 100644
--- a/app/services/post_status_service.rb
+++ b/app/services/post_status_service.rb
@@ -16,7 +16,6 @@ class PostStatusService < BaseService
     process_hashtags_service.call(status)
 
     DistributionWorker.perform_async(status.id)
-    HubPingWorker.perform_async(account.id)
     Pubsubhubbub::DistributionWorker.perform_async(status.stream_entry.id)
 
     status
diff --git a/app/services/reblog_service.rb b/app/services/reblog_service.rb
index 39fdb4ea7..7d0c90d2f 100644
--- a/app/services/reblog_service.rb
+++ b/app/services/reblog_service.rb
@@ -9,7 +9,6 @@ class ReblogService < BaseService
     reblog = account.statuses.create!(reblog: reblogged_status, text: '')
 
     DistributionWorker.perform_async(reblog.id)
-    HubPingWorker.perform_async(account.id)
     Pubsubhubbub::DistributionWorker.perform_async(reblog.stream_entry.id)
 
     if reblogged_status.local?
diff --git a/app/services/remove_status_service.rb b/app/services/remove_status_service.rb
index fa55e668e..836b8fdc5 100644
--- a/app/services/remove_status_service.rb
+++ b/app/services/remove_status_service.rb
@@ -13,7 +13,6 @@ class RemoveStatusService < BaseService
 
     return unless status.account.local?
 
-    HubPingWorker.perform_async(status.account.id)
     Pubsubhubbub::DistributionWorker.perform_async(status.stream_entry.id)
   end
 
diff --git a/app/views/accounts/show.atom.ruby b/app/views/accounts/show.atom.ruby
index b2903d189..a22568396 100644
--- a/app/views/accounts/show.atom.ruby
+++ b/app/views/accounts/show.atom.ruby
@@ -15,7 +15,6 @@ Nokogiri::XML::Builder.new do |xml|
     link_alternate xml, TagManager.instance.url_for(@account)
     link_self      xml, account_url(@account, format: 'atom')
     link_hub       xml, api_push_url
-    link_hub       xml, Rails.configuration.x.hub_url
     link_salmon    xml, api_salmon_url(@account.id)
 
     @entries.each do |stream_entry|
diff --git a/app/views/home/index.html.haml b/app/views/home/index.html.haml
index 498fae105..0adce05bf 100644
--- a/app/views/home/index.html.haml
+++ b/app/views/home/index.html.haml
@@ -1,4 +1,5 @@
 - content_for :header_tags do
+  %meta{:name => "apple-mobile-web-app-capable", :content => "yes"}/
   = javascript_include_tag 'application'
 
 = react_component 'Mastodon', default_props, class: 'app-holder', prerender: false
diff --git a/app/views/layouts/application.html.haml b/app/views/layouts/application.html.haml
index 87f98198c..7e28d27ec 100644
--- a/app/views/layouts/application.html.haml
+++ b/app/views/layouts/application.html.haml
@@ -9,7 +9,6 @@
     %link{:rel => "manifest", :href => "/manifest.json"}/
     %meta{:name => "msapplication-config", :content => "/browserconfig.xml"}/
     %meta{:name => "theme-color", :content => "#2b90d9"}/
-    %meta{:name => "apple-mobile-web-app-capable", :content => "yes"}/
 
     %title
       = "#{yield(:page_title)} - " if content_for?(:page_title)
diff --git a/app/workers/hub_ping_worker.rb b/app/workers/hub_ping_worker.rb
deleted file mode 100644
index 14a151ba0..000000000
--- a/app/workers/hub_ping_worker.rb
+++ /dev/null
@@ -1,12 +0,0 @@
-# frozen_string_literal: true
-
-class HubPingWorker
-  include Sidekiq::Worker
-  include RoutingHelper
-
-  def perform(account_id)
-    account = Account.find(account_id)
-    return unless account.local?
-    OStatus2::Publication.new(account_url(account, format: 'atom'), [Rails.configuration.x.hub_url]).publish
-  end
-end
diff --git a/config/initializers/ostatus.rb b/config/initializers/ostatus.rb
index c5723b2e9..faa9940b0 100644
--- a/config/initializers/ostatus.rb
+++ b/config/initializers/ostatus.rb
@@ -6,7 +6,6 @@ https = ENV['LOCAL_HTTPS'] == 'true'
 
 Rails.application.configure do
   config.x.local_domain = host
-  config.x.hub_url      = ENV.fetch('HUB_URL') { 'https://pubsubhubbub.superfeedr.com' }
   config.x.use_https    = https
   config.x.use_s3       = ENV['S3_ENABLED'] == 'true'
 
diff --git a/spec/controllers/api/v1/follows_controller_spec.rb b/spec/controllers/api/v1/follows_controller_spec.rb
index 1346141fa..97d69ab7b 100644
--- a/spec/controllers/api/v1/follows_controller_spec.rb
+++ b/spec/controllers/api/v1/follows_controller_spec.rb
@@ -18,7 +18,6 @@ RSpec.describe Api::V1::FollowsController, type: :controller do
       stub_request(:get,  "https://quitter.no/avatar/7477-300-20160211190340.png").to_return(request_fixture('avatar.txt'))
       stub_request(:post, "https://quitter.no/main/push/hub").to_return(:status => 200, :body => "", :headers => {})
       stub_request(:post, "https://quitter.no/main/salmon/user/7477").to_return(:status => 200, :body => "", :headers => {})
-      stub_request(:post, "https://pubsubhubbub.superfeedr.com/").to_return(:status => 200, :body => "", :headers => {})
 
       post :create, params: { uri: 'gargron@quitter.no' }
     end
@@ -39,10 +38,6 @@ RSpec.describe Api::V1::FollowsController, type: :controller do
       expect(a_request(:post, "https://quitter.no/main/salmon/user/7477")).to have_been_made
     end
 
-    it 'notifies own hub' do
-      expect(a_request(:post, "https://pubsubhubbub.superfeedr.com/")).to have_been_made
-    end
-
     it 'subscribes to remote hub' do
       expect(a_request(:post, "https://quitter.no/main/push/hub")).to have_been_made
     end
diff --git a/spec/services/reblog_service_spec.rb b/spec/services/reblog_service_spec.rb
index f0a40fe91..5f89169e9 100644
--- a/spec/services/reblog_service_spec.rb
+++ b/spec/services/reblog_service_spec.rb
@@ -8,7 +8,6 @@ RSpec.describe ReblogService do
   subject { ReblogService.new }
 
   before do
-    stub_request(:post, Rails.configuration.x.hub_url)
     stub_request(:post, 'http://salmon.example.com')
 
     subject.(alice, status)
@@ -18,10 +17,6 @@ RSpec.describe ReblogService do
     expect(status.reblogs.count).to eq 1
   end
 
-  it 'pings PubSubHubbub hubs' do
-    expect(a_request(:post, Rails.configuration.x.hub_url)).to have_been_made
-  end
-
   it 'sends a Salmon slap for a remote reblog' do
     expect(a_request(:post, 'http://salmon.example.com')).to have_been_made
   end