diff --git a/.rubocop.yml b/.rubocop.yml
index 14728bf0e..2af0f59bb 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -2,7 +2,8 @@ require:
   - rubocop-rails
 
 AllCops:
-  TargetRubyVersion: 2.4
+  TargetRubyVersion: 2.5
+  NewCops: disable
   Exclude:
   - 'spec/**/*'
   - 'db/**/*'
diff --git a/Dockerfile b/Dockerfile
index 95d45bab4..136b2a35a 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,7 +1,7 @@
 FROM ubuntu:20.04 as build-dep
 
 # Use bash for the shell
-SHELL ["bash", "-c"]
+SHELL ["/usr/bin/bash", "-c"]
 
 # Install Node v12 (LTS)
 ENV NODE_VER="12.20.0"
diff --git a/Gemfile b/Gemfile
index 598b1ffe9..004b3120c 100644
--- a/Gemfile
+++ b/Gemfile
@@ -135,7 +135,7 @@ group :development do
   gem 'active_record_query_trace', '~> 1.8'
   gem 'annotate', '~> 3.1'
   gem 'better_errors', '~> 2.9'
-  gem 'binding_of_caller', '~> 0.7'
+  gem 'binding_of_caller', '~> 1.0'
   gem 'bullet', '~> 6.1'
   gem 'letter_opener', '~> 1.7'
   gem 'letter_opener_web', '~> 1.4'
diff --git a/Gemfile.lock b/Gemfile.lock
index fb06ec207..8d6ce3e0e 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -100,7 +100,7 @@ GEM
       erubi (>= 1.0.0)
       rack (>= 0.9.0)
     bindata (2.4.8)
-    binding_of_caller (0.8.0)
+    binding_of_caller (1.0.0)
       debug_inspector (>= 0.0.1)
     blurhash (0.1.4)
       ffi (~> 1.10.0)
@@ -165,7 +165,7 @@ GEM
     crass (1.0.6)
     css_parser (1.7.1)
       addressable
-    debug_inspector (0.0.3)
+    debug_inspector (1.0.0)
     devise (4.7.3)
       bcrypt (~> 3.0)
       orm_adapter (~> 0.1)
@@ -691,7 +691,7 @@ DEPENDENCIES
   annotate (~> 3.1)
   aws-sdk-s3 (~> 1.87)
   better_errors (~> 2.9)
-  binding_of_caller (~> 0.7)
+  binding_of_caller (~> 1.0)
   blurhash (~> 0.1)
   bootsnap (~> 1.5)
   brakeman (~> 4.10)
diff --git a/Procfile.dev b/Procfile.dev
index e589bbf63..ba04fb661 100644
--- a/Procfile.dev
+++ b/Procfile.dev
@@ -1,4 +1,4 @@
-web: env PORT=3000 bundle exec puma -C config/puma.rb
-sidekiq: env PORT=3000 bundle exec sidekiq
+web: env PORT=3000 RAILS_ENV=development bundle exec puma -C config/puma.rb
+sidekiq: env PORT=3000 RAILS_ENV=development bundle exec sidekiq
 stream: env PORT=4000 yarn run start
 webpack: ./bin/webpack-dev-server --listen-host 0.0.0.0
diff --git a/app/controllers/activitypub/inboxes_controller.rb b/app/controllers/activitypub/inboxes_controller.rb
index d3044f180..92dcb5ac7 100644
--- a/app/controllers/activitypub/inboxes_controller.rb
+++ b/app/controllers/activitypub/inboxes_controller.rb
@@ -5,7 +5,7 @@ class ActivityPub::InboxesController < ActivityPub::BaseController
   include JsonLdHelper
   include AccountOwnedConcern
 
-  before_action :skip_unknown_actor_delete
+  before_action :skip_unknown_actor_activity
   before_action :require_signature!
   skip_before_action :authenticate_user!
 
@@ -18,13 +18,13 @@ class ActivityPub::InboxesController < ActivityPub::BaseController
 
   private
 
-  def skip_unknown_actor_delete
-    head 202 if unknown_deleted_account?
+  def skip_unknown_actor_activity
+    head 202 if unknown_affected_account?
   end
 
-  def unknown_deleted_account?
+  def unknown_affected_account?
     json = Oj.load(body, mode: :strict)
-    json.is_a?(Hash) && json['type'] == 'Delete' && json['actor'].present? && json['actor'] == value_or_id(json['object']) && !Account.where(uri: json['actor']).exists?
+    json.is_a?(Hash) && %w(Delete Update).include?(json['type']) && json['actor'].present? && json['actor'] == value_or_id(json['object']) && !Account.where(uri: json['actor']).exists?
   rescue Oj::ParseError
     false
   end
diff --git a/app/controllers/api/v1/accounts_controller.rb b/app/controllers/api/v1/accounts_controller.rb
index 3e66ff212..953874e1a 100644
--- a/app/controllers/api/v1/accounts_controller.rb
+++ b/app/controllers/api/v1/accounts_controller.rb
@@ -42,7 +42,7 @@ class Api::V1::AccountsController < Api::BaseController
   end
 
   def mute
-    MuteService.new.call(current_user.account, @account, notifications: truthy_param?(:notifications), duration: (params[:duration] || 0))
+    MuteService.new.call(current_user.account, @account, notifications: truthy_param?(:notifications), duration: (params[:duration]&.to_i || 0))
     render json: @account, serializer: REST::RelationshipSerializer, relationships: relationships
   end
 
diff --git a/app/controllers/api/v1/crypto/keys/claims_controller.rb b/app/controllers/api/v1/crypto/keys/claims_controller.rb
index 34b21a380..f9d202d67 100644
--- a/app/controllers/api/v1/crypto/keys/claims_controller.rb
+++ b/app/controllers/api/v1/crypto/keys/claims_controller.rb
@@ -12,7 +12,7 @@ class Api::V1::Crypto::Keys::ClaimsController < Api::BaseController
   private
 
   def set_claim_results
-    @claim_results = devices.map { |device_params| ::Keys::ClaimService.new.call(current_account, device_params[:account_id], device_params[:device_id]) }.compact
+    @claim_results = devices.filter_map { |device_params| ::Keys::ClaimService.new.call(current_account, device_params[:account_id], device_params[:device_id]) }
   end
 
   def resource_params
diff --git a/app/controllers/api/v1/crypto/keys/queries_controller.rb b/app/controllers/api/v1/crypto/keys/queries_controller.rb
index 0851d797d..e6ce9f919 100644
--- a/app/controllers/api/v1/crypto/keys/queries_controller.rb
+++ b/app/controllers/api/v1/crypto/keys/queries_controller.rb
@@ -17,7 +17,7 @@ class Api::V1::Crypto::Keys::QueriesController < Api::BaseController
   end
 
   def set_query_results
-    @query_results = @accounts.map { |account| ::Keys::QueryService.new.call(account) }.compact
+    @query_results = @accounts.filter_map { |account| ::Keys::QueryService.new.call(account) }
   end
 
   def account_ids
diff --git a/app/controllers/concerns/cache_concern.rb b/app/controllers/concerns/cache_concern.rb
index abbdb410a..8d82eda5c 100644
--- a/app/controllers/concerns/cache_concern.rb
+++ b/app/controllers/concerns/cache_concern.rb
@@ -45,7 +45,7 @@ module CacheConcern
       end
     end
 
-    raw.map { |item| cached_keys_with_value[item.id] || uncached[item.id] }.compact
+    raw.filter_map { |item| cached_keys_with_value[item.id] || uncached[item.id] }
   end
 
   def cache_collection_paginated_by_id(raw, klass, limit, options)
diff --git a/app/javascript/mastodon/features/ui/components/focal_point_modal.js b/app/javascript/mastodon/features/ui/components/focal_point_modal.js
index 578375a7f..ffa783e3b 100644
--- a/app/javascript/mastodon/features/ui/components/focal_point_modal.js
+++ b/app/javascript/mastodon/features/ui/components/focal_point_modal.js
@@ -227,7 +227,7 @@ class FocalPointModal extends ImmutablePureComponent {
       const worker = createWorker({
         workerPath: tesseractWorkerPath,
         corePath: tesseractCorePath,
-        langPath: assetHost,
+        langPath: `${assetHost}/ocr/lang-data/`,
         logger: ({ status, progress }) => {
           if (status === 'recognizing text') {
             this.setState({ ocrStatus: 'detecting', progress });
diff --git a/app/lib/activitypub/activity/flag.rb b/app/lib/activitypub/activity/flag.rb
index 1659bc61f..8dfc76f0a 100644
--- a/app/lib/activitypub/activity/flag.rb
+++ b/app/lib/activitypub/activity/flag.rb
@@ -4,8 +4,8 @@ class ActivityPub::Activity::Flag < ActivityPub::Activity
   def perform
     return if skip_reports?
 
-    target_accounts            = object_uris.map { |uri| account_from_uri(uri) }.compact.select(&:local?)
-    target_statuses_by_account = object_uris.map { |uri| status_from_uri(uri) }.compact.select(&:local?).group_by(&:account_id)
+    target_accounts            = object_uris.filter_map { |uri| account_from_uri(uri) }.select(&:local?)
+    target_statuses_by_account = object_uris.filter_map { |uri| status_from_uri(uri) }.select(&:local?).group_by(&:account_id)
 
     target_accounts.each do |target_account|
       target_statuses = target_statuses_by_account[target_account.id]
diff --git a/app/lib/entity_cache.rb b/app/lib/entity_cache.rb
index 89cbf8d2c..e38a3adcd 100644
--- a/app/lib/entity_cache.rb
+++ b/app/lib/entity_cache.rb
@@ -29,7 +29,7 @@ class EntityCache
       uncached.each_value { |item| Rails.cache.write(to_key(:emoji, item.shortcode, domain), item, expires_in: MAX_EXPIRATION) }
     end
 
-    shortcodes.map { |shortcode| cached[to_key(:emoji, shortcode, domain)] || uncached[shortcode] }.compact
+    shortcodes.filter_map { |shortcode| cached[to_key(:emoji, shortcode, domain)] || uncached[shortcode] }
   end
 
   def to_key(type, *ids)
diff --git a/app/lib/spam_check.rb b/app/lib/spam_check.rb
index 652d03615..68e586d00 100644
--- a/app/lib/spam_check.rb
+++ b/app/lib/spam_check.rb
@@ -186,9 +186,9 @@ class SpamCheck
 
   def matching_status_ids
     if nilsimsa?
-      other_digests.select { |record| record.start_with?('nilsimsa') && nilsimsa_compare_value(digest, record.split(':')[1]) >= NILSIMSA_COMPARE_THRESHOLD }.map { |record| record.split(':')[2] }.compact
+      other_digests.select { |record| record.start_with?('nilsimsa') && nilsimsa_compare_value(digest, record.split(':')[1]) >= NILSIMSA_COMPARE_THRESHOLD }.filter_map { |record| record.split(':')[2] }
     else
-      other_digests.select { |record| record.start_with?('md5') && record.split(':')[1] == digest }.map { |record| record.split(':')[2] }.compact
+      other_digests.select { |record| record.start_with?('md5') && record.split(':')[1] == digest }.filter_map { |record| record.split(':')[2] }
     end
   end
 
diff --git a/app/models/account.rb b/app/models/account.rb
index f6aba74c6..15bd8a917 100644
--- a/app/models/account.rb
+++ b/app/models/account.rb
@@ -387,15 +387,17 @@ class Account < ApplicationRecord
   end
 
   class Field < ActiveModelSerializers::Model
-    attributes :name, :value, :verified_at, :account, :errors
+    attributes :name, :value, :verified_at, :account
 
     def initialize(account, attributes)
-      @account     = account
-      @attributes  = attributes
-      @name        = attributes['name'].strip[0, string_limit]
-      @value       = attributes['value'].strip[0, string_limit]
-      @verified_at = attributes['verified_at']&.to_datetime
-      @errors      = {}
+      @original_field = attributes
+      string_limit = account.local? ? 255 : 2047
+      super(
+        account:     account,
+        name:        attributes['name'].strip[0, string_limit],
+        value:       attributes['value'].strip[0, string_limit],
+        verified_at: attributes['verified_at']&.to_datetime,
+      )
     end
 
     def verified?
@@ -417,22 +419,12 @@ class Account < ApplicationRecord
     end
 
     def mark_verified!
-      @verified_at = Time.now.utc
-      @attributes['verified_at'] = @verified_at
+      self.verified_at = Time.now.utc
+      @original_field['verified_at'] = verified_at
     end
 
     def to_h
-      { name: @name, value: @value, verified_at: @verified_at }
-    end
-
-    private
-
-    def string_limit
-      if account.local?
-        255
-      else
-        2047
-      end
+      { name: name, value: value, verified_at: verified_at }
     end
   end
 
@@ -518,7 +510,7 @@ class Account < ApplicationRecord
     def from_text(text)
       return [] if text.blank?
 
-      text.scan(MENTION_RE).map { |match| match.first.split('@', 2) }.uniq.map do |(username, domain)|
+      text.scan(MENTION_RE).map { |match| match.first.split('@', 2) }.uniq.filter_map do |(username, domain)|
         domain = begin
           if TagManager.instance.local_domain?(domain)
             nil
@@ -527,7 +519,7 @@ class Account < ApplicationRecord
           end
         end
         EntityCache.instance.mention(username, domain)
-      end.compact
+      end
     end
 
     private
diff --git a/app/models/concerns/status_threading_concern.rb b/app/models/concerns/status_threading_concern.rb
index a0ead1995..5c04108e4 100644
--- a/app/models/concerns/status_threading_concern.rb
+++ b/app/models/concerns/status_threading_concern.rb
@@ -83,7 +83,7 @@ module StatusThreadingConcern
   def find_statuses_from_tree_path(ids, account, promote: false)
     statuses    = Status.with_accounts(ids).to_a
     account_ids = statuses.map(&:account_id).uniq
-    domains     = statuses.map(&:account_domain).compact.uniq
+    domains     = statuses.filter_map(&:account_domain).uniq
     relations   = relations_map_for_account(account, account_ids, domains)
 
     statuses.reject! { |status| StatusFilter.new(status, account, relations).filtered? }
diff --git a/app/models/custom_filter.rb b/app/models/custom_filter.rb
index 8df8a4fbf..9d0f3729b 100644
--- a/app/models/custom_filter.rb
+++ b/app/models/custom_filter.rb
@@ -46,7 +46,7 @@ class CustomFilter < ApplicationRecord
   private
 
   def clean_up_contexts
-    self.context = Array(context).map(&:strip).map(&:presence).compact
+    self.context = Array(context).map(&:strip).filter_map(&:presence)
   end
 
   def remove_cache
diff --git a/app/models/home_feed.rb b/app/models/home_feed.rb
index 0fe9dae46..d6ebb5fa6 100644
--- a/app/models/home_feed.rb
+++ b/app/models/home_feed.rb
@@ -2,12 +2,11 @@
 
 class HomeFeed < Feed
   def initialize(account)
-    @type    = :home
-    @id      = account.id
     @account = account
+    super(:home, account.id)
   end
 
   def regenerating?
-    redis.exists?("account:#{@id}:regeneration")
+    redis.exists?("account:#{@account.id}:regeneration")
   end
 end
diff --git a/app/models/list_feed.rb b/app/models/list_feed.rb
index f371e4ed9..47b9281b8 100644
--- a/app/models/list_feed.rb
+++ b/app/models/list_feed.rb
@@ -2,7 +2,6 @@
 
 class ListFeed < Feed
   def initialize(list)
-    @type    = :list
-    @id      = list.id
+    super(:list, list.id)
   end
 end
diff --git a/app/models/notification.rb b/app/models/notification.rb
index e83123c97..b6db37d6d 100644
--- a/app/models/notification.rb
+++ b/app/models/notification.rb
@@ -92,7 +92,7 @@ class Notification < ApplicationRecord
     end
 
     def reload_stale_associations!(cached_items)
-      account_ids = (cached_items.map(&:from_account_id) + cached_items.map { |item| item.target_status&.account_id }.compact).uniq
+      account_ids = (cached_items.map(&:from_account_id) + cached_items.filter_map { |item| item.target_status&.account_id }).uniq
 
       return if account_ids.empty?
 
diff --git a/app/models/poll.rb b/app/models/poll.rb
index e1ca55252..d2a17277b 100644
--- a/app/models/poll.rb
+++ b/app/models/poll.rb
@@ -73,10 +73,12 @@ class Poll < ApplicationRecord
     attributes :id, :title, :votes_count, :poll
 
     def initialize(poll, id, title, votes_count)
-      @poll        = poll
-      @id          = id
-      @title       = title
-      @votes_count = votes_count
+      super(
+        poll:        poll,
+        id:          id,
+        title:       title,
+        votes_count: votes_count,
+      )
     end
   end
 
diff --git a/app/models/public_feed.rb b/app/models/public_feed.rb
index 2839da5cb..2528ef1b6 100644
--- a/app/models/public_feed.rb
+++ b/app/models/public_feed.rb
@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 
-class PublicFeed < Feed
+class PublicFeed
   # @param [Account] account
   # @param [Hash] options
   # @option [Boolean] :with_replies
@@ -35,36 +35,38 @@ class PublicFeed < Feed
 
   private
 
+  attr_reader :account, :options
+
   def allow_local_only?
-    local_account? && (local_only? || @options[:allow_local_only])
+    local_account? && (local_only? || options[:allow_local_only])
   end
 
   def with_reblogs?
-    @options[:with_reblogs]
+    options[:with_reblogs]
   end
 
   def with_replies?
-    @options[:with_replies]
+    options[:with_replies]
   end
 
   def local_only?
-    @options[:local]
+    options[:local]
   end
 
   def remote_only?
-    @options[:remote]
+    options[:remote]
   end
 
   def account?
-    @account.present?
+    account.present?
   end
 
   def local_account?
-    @account&.local?
+    account&.local?
   end
 
   def media_only?
-    @options[:only_media]
+    options[:only_media]
   end
 
   def public_scope
@@ -96,9 +98,9 @@ class PublicFeed < Feed
   end
 
   def account_filters_scope
-    Status.not_excluded_by_account(@account).tap do |scope|
-      scope.merge!(Status.not_domain_blocked_by_account(@account)) unless local_only?
-      scope.merge!(Status.in_chosen_languages(@account)) if @account.chosen_languages.present?
+    Status.not_excluded_by_account(account).tap do |scope|
+      scope.merge!(Status.not_domain_blocked_by_account(account)) unless local_only?
+      scope.merge!(Status.in_chosen_languages(account)) if account.chosen_languages.present?
     end
   end
 end
diff --git a/app/models/status.rb b/app/models/status.rb
index 0d15304b6..766c13a40 100644
--- a/app/models/status.rb
+++ b/app/models/status.rb
@@ -387,7 +387,7 @@ class Status < ApplicationRecord
     def from_text(text)
       return [] if text.blank?
 
-      text.scan(FetchLinkCardService::URL_PATTERN).map(&:first).uniq.map do |url|
+      text.scan(FetchLinkCardService::URL_PATTERN).map(&:first).uniq.filter_map do |url|
         status = begin
           if TagManager.instance.local_url?(url)
             ActivityPub::TagManager.instance.uri_to_resource(url, Status)
@@ -396,7 +396,7 @@ class Status < ApplicationRecord
           end
         end
         status&.distributable? ? status : nil
-      end.compact
+      end
     end
   end
 
diff --git a/app/models/tag_feed.rb b/app/models/tag_feed.rb
index a7d583a7e..fbbdbaae2 100644
--- a/app/models/tag_feed.rb
+++ b/app/models/tag_feed.rb
@@ -13,9 +13,8 @@ class TagFeed < PublicFeed
   # @option [Boolean] :remote
   # @option [Boolean] :only_media
   def initialize(tag, account, options = {})
-    @tag     = tag
-    @account = account
-    @options = options
+    @tag = tag
+    super(account, options)
   end
 
   # @param [Integer] limit
@@ -41,15 +40,15 @@ class TagFeed < PublicFeed
   private
 
   def tagged_with_any_scope
-    Status.group(:id).tagged_with(tags_for(Array(@tag.name) | Array(@options[:any])))
+    Status.group(:id).tagged_with(tags_for(Array(@tag.name) | Array(options[:any])))
   end
 
   def tagged_with_all_scope
-    Status.group(:id).tagged_with_all(tags_for(@options[:all]))
+    Status.group(:id).tagged_with_all(tags_for(options[:all]))
   end
 
   def tagged_with_none_scope
-    Status.group(:id).tagged_with_none(tags_for(@options[:none]))
+    Status.group(:id).tagged_with_none(tags_for(options[:none]))
   end
 
   def tags_for(names)
diff --git a/app/presenters/status_relationships_presenter.rb b/app/presenters/status_relationships_presenter.rb
index 3cc905a75..f4849d245 100644
--- a/app/presenters/status_relationships_presenter.rb
+++ b/app/presenters/status_relationships_presenter.rb
@@ -14,7 +14,7 @@ class StatusRelationshipsPresenter
     else
       statuses            = statuses.compact
       status_ids          = statuses.flat_map { |s| [s.id, s.reblog_of_id] }.uniq.compact
-      conversation_ids    = statuses.map(&:conversation_id).compact.uniq
+      conversation_ids    = statuses.filter_map(&:conversation_id).uniq
       pinnable_status_ids = statuses.map(&:proper).select { |s| s.account_id == current_account_id && %w(public unlisted).include?(s.visibility) }.map(&:id)
 
       @reblogs_map     = Status.reblogs_map(status_ids, current_account_id).merge(options[:reblogs_map] || {})
diff --git a/app/services/activitypub/fetch_featured_collection_service.rb b/app/services/activitypub/fetch_featured_collection_service.rb
index 2c2770466..82c861f5b 100644
--- a/app/services/activitypub/fetch_featured_collection_service.rb
+++ b/app/services/activitypub/fetch_featured_collection_service.rb
@@ -24,8 +24,7 @@ class ActivityPub::FetchFeaturedCollectionService < BaseService
   def process_items(items)
     status_ids = items.map { |item| value_or_id(item) }
                       .reject { |uri| ActivityPub::TagManager.instance.local_uri?(uri) }
-                      .map { |uri| ActivityPub::FetchRemoteStatusService.new.call(uri) }
-                      .compact
+                      .filter_map { |uri| ActivityPub::FetchRemoteStatusService.new.call(uri) }
                       .select { |status| status.account_id == @account.id }
                       .map(&:id)
 
diff --git a/app/services/activitypub/process_collection_service.rb b/app/services/activitypub/process_collection_service.rb
index f1d175dac..170e6709c 100644
--- a/app/services/activitypub/process_collection_service.rb
+++ b/app/services/activitypub/process_collection_service.rb
@@ -37,7 +37,7 @@ class ActivityPub::ProcessCollectionService < BaseService
   end
 
   def process_items(items)
-    items.reverse_each.map { |item| process_item(item) }.compact
+    items.reverse_each.filter_map { |item| process_item(item) }
   end
 
   def supported_context?
diff --git a/app/services/activitypub/process_poll_service.rb b/app/services/activitypub/process_poll_service.rb
index 903b6a78a..d83e614d8 100644
--- a/app/services/activitypub/process_poll_service.rb
+++ b/app/services/activitypub/process_poll_service.rb
@@ -30,7 +30,7 @@ class ActivityPub::ProcessPollService < BaseService
 
     voters_count = @json['votersCount']
 
-    latest_options = items.map { |item| item['name'].presence || item['content'] }.compact
+    latest_options = items.filter_map { |item| item['name'].presence || item['content'] }
 
     # If for some reasons the options were changed, it invalidates all previous
     # votes, so we need to remove them
diff --git a/app/services/activitypub/synchronize_followers_service.rb b/app/services/activitypub/synchronize_followers_service.rb
index d83fcf55e..93cd60253 100644
--- a/app/services/activitypub/synchronize_followers_service.rb
+++ b/app/services/activitypub/synchronize_followers_service.rb
@@ -14,7 +14,7 @@ class ActivityPub::SynchronizeFollowersService < BaseService
     # should never happen in practice, since in almost all cases we keep an
     # Account record, and should we not do that, we should have sent a Delete.
     # In any case there is not much we can do if that occurs.
-    @expected_followers = items.map { |uri| ActivityPub::TagManager.instance.uri_to_resource(uri, Account) }.compact
+    @expected_followers = items.filter_map { |uri| ActivityPub::TagManager.instance.uri_to_resource(uri, Account) }
 
     remove_unexpected_local_followers!
     handle_unexpected_outgoing_follows!
diff --git a/app/services/fetch_link_card_service.rb b/app/services/fetch_link_card_service.rb
index 7efa31054..255490d5c 100644
--- a/app/services/fetch_link_card_service.rb
+++ b/app/services/fetch_link_card_service.rb
@@ -67,7 +67,7 @@ class FetchLinkCardService < BaseService
     else
       html  = Nokogiri::HTML(@status.text)
       links = html.css('a')
-      urls  = links.map { |a| Addressable::URI.parse(a['href']) unless skip_link?(a) }.compact.map(&:normalize).compact
+      urls  = links.filter_map { |a| Addressable::URI.parse(a['href']) unless skip_link?(a) }.filter_map(&:normalize)
     end
 
     urls.reject { |uri| bad_url?(uri) }.first
diff --git a/app/services/import_service.rb b/app/services/import_service.rb
index 0c6ef2238..b11532283 100644
--- a/app/services/import_service.rb
+++ b/app/services/import_service.rb
@@ -107,12 +107,12 @@ class ImportService < BaseService
       end
     end
 
-    statuses = items.map do |uri|
+    statuses = items.filter_map do |uri|
       status = ActivityPub::TagManager.instance.uri_to_resource(uri, Status)
       next if status.nil? && ActivityPub::TagManager.instance.local_uri?(uri)
 
       status || ActivityPub::FetchRemoteStatusService.new.call(uri)
-    end.compact
+    end
 
     account_ids         = statuses.map(&:account_id)
     preloaded_relations = relations_map_for_account(@account, account_ids)
diff --git a/app/services/keys/claim_service.rb b/app/services/keys/claim_service.rb
index 672119130..69568a0d1 100644
--- a/app/services/keys/claim_service.rb
+++ b/app/services/keys/claim_service.rb
@@ -8,11 +8,13 @@ class Keys::ClaimService < BaseService
                :key, :signature
 
     def initialize(account, device_id, key_attributes = {})
-      @account   = account
-      @device_id = device_id
-      @key_id    = key_attributes[:key_id]
-      @key       = key_attributes[:key]
-      @signature = key_attributes[:signature]
+      super(
+        account:   account,
+        device_id: device_id,
+        key_id:    key_attributes[:key_id],
+        key:       key_attributes[:key],
+        signature: key_attributes[:signature],
+      )
     end
   end
 
diff --git a/app/services/keys/query_service.rb b/app/services/keys/query_service.rb
index 286fbd834..ac3388bdc 100644
--- a/app/services/keys/query_service.rb
+++ b/app/services/keys/query_service.rb
@@ -7,8 +7,10 @@ class Keys::QueryService < BaseService
     attributes :account, :devices
 
     def initialize(account, devices)
-      @account = account
-      @devices = devices || []
+      super(
+        account: account,
+        devices: devices || [],
+      )
     end
 
     def find(device_id)
@@ -20,11 +22,13 @@ class Keys::QueryService < BaseService
     attributes :device_id, :name, :identity_key, :fingerprint_key
 
     def initialize(attributes = {})
-      @device_id       = attributes[:device_id]
-      @name            = attributes[:name]
-      @identity_key    = attributes[:identity_key]
-      @fingerprint_key = attributes[:fingerprint_key]
-      @claim_url       = attributes[:claim_url]
+      super(
+        device_id:       attributes[:device_id],
+        name:            attributes[:name],
+        identity_key:    attributes[:identity_key],
+        fingerprint_key: attributes[:fingerprint_key],
+      )
+      @claim_url = attributes[:claim_url]
     end
 
     def valid_claim_url?
diff --git a/app/validators/existing_username_validator.rb b/app/validators/existing_username_validator.rb
index b31d09827..723302ec9 100644
--- a/app/validators/existing_username_validator.rb
+++ b/app/validators/existing_username_validator.rb
@@ -5,7 +5,7 @@ class ExistingUsernameValidator < ActiveModel::EachValidator
     return if value.blank?
 
     if options[:multiple]
-      missing_usernames = value.split(',').map { |username| username.strip.gsub(/\A@/, '') }.map { |username| username unless Account.find_local(username) }.compact
+      missing_usernames = value.split(',').map { |username| username.strip.gsub(/\A@/, '') }.filter_map { |username| username unless Account.find_local(username) }
       record.errors.add(attribute, I18n.t('existing_username_validator.not_found_multiple', usernames: missing_usernames.join(', '))) if missing_usernames.any?
     else
       record.errors.add(attribute, I18n.t('existing_username_validator.not_found')) unless Account.find_local(value.strip.gsub(/\A@/, ''))
diff --git a/config/application.rb b/config/application.rb
index af7735221..696dc17e6 100644
--- a/config/application.rb
+++ b/config/application.rb
@@ -7,6 +7,7 @@ require 'rails/all'
 Bundler.require(*Rails.groups)
 
 require_relative '../app/lib/exceptions'
+require_relative '../lib/enumerable'
 require_relative '../lib/redis/namespace_extensions'
 require_relative '../lib/paperclip/url_generator_extensions'
 require_relative '../lib/paperclip/attachment_extensions'
diff --git a/config/initializers/omniauth.rb b/config/initializers/omniauth.rb
index e8d7697a1..9e037f421 100644
--- a/config/initializers/omniauth.rb
+++ b/config/initializers/omniauth.rb
@@ -60,6 +60,7 @@ Devise.setup do |config|
     saml_options[:attribute_statements][:verified] = [ENV['SAML_ATTRIBUTES_STATEMENTS_VERIFIED']] if ENV['SAML_ATTRIBUTES_STATEMENTS_VERIFIED']
     saml_options[:attribute_statements][:verified_email] = [ENV['SAML_ATTRIBUTES_STATEMENTS_VERIFIED_EMAIL']] if ENV['SAML_ATTRIBUTES_STATEMENTS_VERIFIED_EMAIL']
     saml_options[:uid_attribute] = ENV['SAML_UID_ATTRIBUTE'] if ENV['SAML_UID_ATTRIBUTE']
+    saml_options[:allowed_clock_drift] = ENV['SAML_ALLOWED_CLOCK_DRIFT'] if ENV['SAML_ALLOWED_CLOCK_DRIFT']
     config.omniauth :saml, saml_options
   end
 end
diff --git a/config/locales/devise.en.yml b/config/locales/devise.en.yml
index a3f2c5796..cc4140d14 100644
--- a/config/locales/devise.en.yml
+++ b/config/locales/devise.en.yml
@@ -68,7 +68,7 @@ en:
         deleted:
           explanation: The following security key has been deleted from your account
           subject: 'Mastodon: Security key deleted'
-          title: One of you security keys has been deleted
+          title: One of your security keys has been deleted
       webauthn_disabled:
         explanation: Authentication with security keys has been disabled for your account. Login is now possible using only the token generated by the paired TOTP app.
         subject: 'Mastodon: Authentication with security keys disabled'
diff --git a/lib/enumerable.rb b/lib/enumerable.rb
new file mode 100644
index 000000000..66918f65e
--- /dev/null
+++ b/lib/enumerable.rb
@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+module Enumerable
+  # TODO: Remove this once stop to support Ruby 2.6
+  if RUBY_VERSION < '2.7.0'
+    def filter_map
+      if block_given?
+        result = []
+        each do |element|
+          res = yield element
+          result << res if res
+        end
+        result
+      else
+        Enumerator.new do |yielder|
+          result = []
+          each do |element|
+            res = yielder.yield element
+            result << res if res
+          end
+          result
+        end
+      end
+    end
+  end
+end
diff --git a/lib/mastodon/maintenance_cli.rb b/lib/mastodon/maintenance_cli.rb
index 822051ceb..029d42a05 100644
--- a/lib/mastodon/maintenance_cli.rb
+++ b/lib/mastodon/maintenance_cli.rb
@@ -160,6 +160,7 @@ module Mastodon
       deduplicate_tags!
       deduplicate_webauthn_credentials!
 
+      Scenic.database.refresh_materialized_view('instances', concurrently: true, cascade: false) if ActiveRecord::Migrator.current_version >= 2020_12_06_004238
       Rails.cache.clear
 
       @prompt.say 'Finished!'
@@ -188,6 +189,11 @@ module Mastodon
       else
         ActiveRecord::Base.connection.add_index :accounts, "lower (username), COALESCE(lower(domain), '')", name: 'index_accounts_on_username_and_domain_lower', unique: true
       end
+
+      @prompt.say 'Reindexing textual indexes on accounts…'
+      ActiveRecord::Base.connection.execute('REINDEX INDEX search_index;')
+      ActiveRecord::Base.connection.execute('REINDEX INDEX index_accounts_on_uri;')
+      ActiveRecord::Base.connection.execute('REINDEX INDEX index_accounts_on_url;')
     end
 
     def deduplicate_users!
diff --git a/lib/paperclip/attachment_extensions.rb b/lib/paperclip/attachment_extensions.rb
index 94f7769b6..e25a34213 100644
--- a/lib/paperclip/attachment_extensions.rb
+++ b/lib/paperclip/attachment_extensions.rb
@@ -27,7 +27,7 @@ module Paperclip
       return true  if original_filename == other_filename
       return false if original_filename.nil?
 
-      formats = styles.values.map(&:format).compact
+      formats = styles.values.filter_map(&:format)
 
       return false if formats.empty?
 
diff --git a/lib/paperclip/color_extractor.rb b/lib/paperclip/color_extractor.rb
index f850dc067..a70a3d21f 100644
--- a/lib/paperclip/color_extractor.rb
+++ b/lib/paperclip/color_extractor.rb
@@ -142,7 +142,7 @@ module Paperclip
       g = 0.0
       b = 0.0
 
-      if s == 0.0
+      if s.zero?
         r = l.to_f
         g = l.to_f
         b = l.to_f # achromatic
diff --git a/package.json b/package.json
index caf9a99b6..98f8b6d83 100644
--- a/package.json
+++ b/package.json
@@ -167,7 +167,7 @@
     "tiny-queue": "^0.2.1",
     "uuid": "^8.3.1",
     "webpack": "^4.44.2",
-    "webpack-assets-manifest": "^3.1.1",
+    "webpack-assets-manifest": "^4.0.0",
     "webpack-bundle-analyzer": "^4.3.0",
     "webpack-cli": "^3.3.12",
     "webpack-merge": "^5.7.3",
diff --git a/spec/controllers/api/v1/accounts_controller_spec.rb b/spec/controllers/api/v1/accounts_controller_spec.rb
index 1e656503f..d9ee37ffa 100644
--- a/spec/controllers/api/v1/accounts_controller_spec.rb
+++ b/spec/controllers/api/v1/accounts_controller_spec.rb
@@ -268,6 +268,34 @@ RSpec.describe Api::V1::AccountsController, type: :controller do
     it_behaves_like 'forbidden for wrong scope', 'read:accounts'
   end
 
+  describe 'POST #mute with nonzero duration set' do
+    let(:scopes) { 'write:mutes' }
+    let(:other_account) { Fabricate(:user, email: 'bob@example.com', account: Fabricate(:account, username: 'bob')).account }
+
+    before do
+      user.account.follow!(other_account)
+      post :mute, params: { id: other_account.id, duration: 300 }
+    end
+
+    it 'returns http success' do
+      expect(response).to have_http_status(200)
+    end
+
+    it 'does not remove the following relation between user and target user' do
+      expect(user.account.following?(other_account)).to be true
+    end
+
+    it 'creates a muting relation' do
+      expect(user.account.muting?(other_account)).to be true
+    end
+
+    it 'mutes notifications' do
+      expect(user.account.muting_notifications?(other_account)).to be true
+    end
+
+    it_behaves_like 'forbidden for wrong scope', 'read:accounts'
+  end
+
   describe 'POST #unmute' do
     let(:scopes) { 'write:mutes' }
     let(:other_account) { Fabricate(:user, email: 'bob@example.com', account: Fabricate(:account, username: 'bob')).account }
diff --git a/yarn.lock b/yarn.lock
index 91270c11c..df415f517 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2798,7 +2798,7 @@ chalk@^1.0.0, chalk@^1.1.1, chalk@^1.1.3:
     strip-ansi "^3.0.0"
     supports-color "^2.0.0"
 
-chalk@^2.0, chalk@^2.0.0, chalk@^2.3.2, chalk@^2.4.1, chalk@^2.4.2:
+chalk@^2.0.0, chalk@^2.3.2, chalk@^2.4.1, chalk@^2.4.2:
   version "2.4.2"
   resolved "https://registry.yarnpkg.com/chalk/-/chalk-2.4.2.tgz#cd42541677a54333cf541a49108c1432b44c9424"
   integrity sha512-Mti+f9lpJNcwF4tWV8/OrTTtF1gZi+f8FqlyAdouralcFWFQWF2+NgCHShjkCb+IFBLq9buZwE1xckQU4peSuQ==
@@ -2815,7 +2815,7 @@ chalk@^3.0.0:
     ansi-styles "^4.1.0"
     supports-color "^7.1.0"
 
-chalk@^4.0.0, chalk@^4.1.0:
+chalk@^4.0, chalk@^4.0.0, chalk@^4.1.0:
   version "4.1.0"
   resolved "https://registry.yarnpkg.com/chalk/-/chalk-4.1.0.tgz#4e14870a618d9e2edd97dd8345fd9d9dc315646a"
   integrity sha512-qwx12AxXe2Q5xQ43Ac//I6v5aXTipYrSESdOgzrN+9XjgEpyjpKuvSGaN4qE93f7TQTlerQQ8S+EQ0EyDoVL1A==
@@ -6831,6 +6831,13 @@ locate-path@^5.0.0:
   dependencies:
     p-locate "^4.1.0"
 
+lockfile@^1.0.4:
+  version "1.0.4"
+  resolved "https://registry.yarnpkg.com/lockfile/-/lockfile-1.0.4.tgz#07f819d25ae48f87e538e6578b6964a4981a5609"
+  integrity sha512-cvbTwETRfsFh4nHsL1eGWapU1XFi5Ot9E85sWAwia7Y7EgB7vfqcZhTKZ+l7hCGxSPoushMv5GKhT5PdLv03WA==
+  dependencies:
+    signal-exit "^3.0.2"
+
 lodash.capitalize@^4.1.0:
   version "4.2.1"
   resolved "https://registry.yarnpkg.com/lodash.capitalize/-/lodash.capitalize-4.2.1.tgz#f826c9b4e2a8511d84e3aca29db05e1a4f3b72a9"
@@ -6841,6 +6848,11 @@ lodash.defaults@^4.0.1:
   resolved "https://registry.yarnpkg.com/lodash.defaults/-/lodash.defaults-4.2.0.tgz#d09178716ffea4dde9e5fb7b37f6f0802274580c"
   integrity sha1-0JF4cW/+pN3p5ft7N/bwgCJ0WAw=
 
+lodash.escaperegexp@^4.0:
+  version "4.1.2"
+  resolved "https://registry.yarnpkg.com/lodash.escaperegexp/-/lodash.escaperegexp-4.1.2.tgz#64762c48618082518ac3df4ccf5d5886dae20347"
+  integrity sha1-ZHYsSGGAglGKw99Mz11YhtriA0c=
+
 lodash.get@^4.0:
   version "4.4.2"
   resolved "https://registry.yarnpkg.com/lodash.get/-/lodash.get-4.4.2.tgz#2d177f652fa31e939b4438d5341499dfa3825e99"
@@ -7199,14 +7211,14 @@ mixin-deep@^1.2.0:
     for-in "^1.0.2"
     is-extendable "^1.0.1"
 
-mkdirp@^0.5, mkdirp@^0.5.0, mkdirp@^0.5.1, mkdirp@^0.5.3, mkdirp@^0.5.5, mkdirp@~0.5.1:
+mkdirp@^0.5.0, mkdirp@^0.5.1, mkdirp@^0.5.3, mkdirp@^0.5.5, mkdirp@~0.5.1:
   version "0.5.5"
   resolved "https://registry.yarnpkg.com/mkdirp/-/mkdirp-0.5.5.tgz#d91cefd62d1436ca0f41620e251288d420099def"
   integrity sha512-NKmAlESf6jMGym1++R0Ra7wvhV+wFW63FaSOFPwRahvea0gMUcGUhVeAg/0BC0wiv9ih5NYPB1Wn1UEI1/L+xQ==
   dependencies:
     minimist "^1.2.5"
 
-mkdirp@^1.0.3, mkdirp@^1.0.4:
+mkdirp@^1.0, mkdirp@^1.0.3, mkdirp@^1.0.4:
   version "1.0.4"
   resolved "https://registry.yarnpkg.com/mkdirp/-/mkdirp-1.0.4.tgz#3eb5ed62622756d79a5f0e2a221dfebad75c2f7e"
   integrity sha512-vVqVZQyf3WLx2Shd0qJ9xuvqgAyKPLAiqITEtqW0oIUjzo3PePDd6fW9iFz30ef7Ysp/oiWqbhszeGWW2T6Gzw==
@@ -9561,7 +9573,7 @@ schema-utils@^2.2.0, schema-utils@^2.6.5:
     ajv "^6.12.4"
     ajv-keywords "^3.5.2"
 
-schema-utils@^3.0.0:
+schema-utils@^3.0, schema-utils@^3.0.0:
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/schema-utils/-/schema-utils-3.0.0.tgz#67502f6aa2b66a2d4032b4279a2944978a0913ef"
   integrity sha512-6D82/xSzO094ajanoOSbe4YvXWMfn2A//8Y1+MUqFAJul5Bs+yn36xbK9OtNDcRVSBJ9jjeoXftM6CfztsjOAA==
@@ -10377,7 +10389,7 @@ table@^6.0.4:
     slice-ansi "^4.0.0"
     string-width "^4.2.0"
 
-tapable@^1.0.0, tapable@^1.1.3:
+tapable@^1.0, tapable@^1.0.0, tapable@^1.1.3:
   version "1.1.3"
   resolved "https://registry.yarnpkg.com/tapable/-/tapable-1.1.3.tgz#a1fccc06b58db61fd7a45da2da44f5f3a3e67ba2"
   integrity sha512-4WK/bYZmj8xLr+HUCODHGF1ZFzsYffasLUgEiMBY4fgtltdO6B4WJtlSbPaDTLpYTcGVwM2qLnFTICEcNxs3kA==
@@ -11051,18 +11063,21 @@ webidl-conversions@^6.1.0:
   resolved "https://registry.yarnpkg.com/webidl-conversions/-/webidl-conversions-6.1.0.tgz#9111b4d7ea80acd40f5270d666621afa78b69514"
   integrity sha512-qBIvFLGiBpLjfwmYAaHPXsn+ho5xZnGvyGvsarywGNc8VyQJUMHJ8OBKGGrPER0okBeMDaan4mNBlgBROxuI8w==
 
-webpack-assets-manifest@^3.1.1:
-  version "3.1.1"
-  resolved "https://registry.yarnpkg.com/webpack-assets-manifest/-/webpack-assets-manifest-3.1.1.tgz#39bbc3bf2ee57fcd8ba07cda51c9ba4a3c6ae1de"
-  integrity sha512-JV9V2QKc5wEWQptdIjvXDUL1ucbPLH2f27toAY3SNdGZp+xSaStAgpoMcvMZmqtFrBc9a5pTS1058vxyMPOzRQ==
+webpack-assets-manifest@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/webpack-assets-manifest/-/webpack-assets-manifest-4.0.0.tgz#6c906f6a77945aa326822e158f22d172ccc59f0f"
+  integrity sha512-zbozd1Cr6gS5XMWWHfISusocOO2bO05ktpJXWdoYtv12/FSXsNqyVjNwLE9ehBXDsEOwRtqd3kPDdTZKFjjD/w==
   dependencies:
-    chalk "^2.0"
+    chalk "^4.0"
+    deepmerge "^4.2.2"
+    lockfile "^1.0.4"
+    lodash.escaperegexp "^4.0"
     lodash.get "^4.0"
     lodash.has "^4.0"
-    mkdirp "^0.5"
-    schema-utils "^1.0.0"
-    tapable "^1.0.0"
-    webpack-sources "^1.0.0"
+    mkdirp "^1.0"
+    schema-utils "^3.0"
+    tapable "^1.0"
+    webpack-sources "^1.0"
 
 webpack-bundle-analyzer@^4.3.0:
   version "4.3.0"
@@ -11162,7 +11177,7 @@ webpack-merge@^5.7.3:
     clone-deep "^4.0.1"
     wildcard "^2.0.0"
 
-webpack-sources@^1.0.0, webpack-sources@^1.1.0, webpack-sources@^1.4.0, webpack-sources@^1.4.1, webpack-sources@^1.4.3:
+webpack-sources@^1.0, webpack-sources@^1.1.0, webpack-sources@^1.4.0, webpack-sources@^1.4.1, webpack-sources@^1.4.3:
   version "1.4.3"
   resolved "https://registry.yarnpkg.com/webpack-sources/-/webpack-sources-1.4.3.tgz#eedd8ec0b928fbf1cbfe994e22d2d890f330a933"
   integrity sha512-lgTS3Xhv1lCOKo7SA5TjKXMjpSM4sBjNV5+q2bqesbSPs5FjGmU6jjtBSkX9b4qW87vDIsCIlUPOEhbZrMdjeQ==