diff --git a/.env.production.sample b/.env.production.sample
index 7bcce0f7e5..5939c12146 100644
--- a/.env.production.sample
+++ b/.env.production.sample
@@ -251,6 +251,11 @@ SMTP_FROM_ADDRESS=notifications@example.com
 # Maximum allowed character count
 MAX_TOOT_CHARS=500
 
+# Maximum allowed hashtags to follow in a feed column
+# Note that setting this value higher may cause significant
+# database load
+MAX_FEED_HASHTAGS=4
+
 # Maximum number of pinned posts
 MAX_PINNED_TOOTS=5
 
diff --git a/.github/workflows/build-security.yml b/.github/workflows/build-security.yml
index 6fca326198..e9f1862f5d 100644
--- a/.github/workflows/build-security.yml
+++ b/.github/workflows/build-security.yml
@@ -36,7 +36,7 @@ jobs:
       tags: |
         type=raw,value=edge
         type=raw,value=nightly
-        type=schedule,pattern=${{ needs.compute-suffix.outputs.prerelease }}
+        type=raw,value=${{ needs.compute-suffix.outputs.prerelease }}
     secrets: inherit
 
   build-image-streaming:
@@ -48,7 +48,7 @@ jobs:
       use_native_arm64_builder: false
       cache: false
       push_to_images: |
-        ghcr.io/${{ github.repository_owner }}/mastodon
+        ghcr.io/${{ github.repository_owner }}/mastodon-streaming
       version_prerelease: ${{ needs.compute-suffix.outputs.prerelease }}
       labels: |
         org.opencontainers.image.description=Nightly build image used for testing purposes
@@ -57,5 +57,5 @@ jobs:
       tags: |
         type=raw,value=edge
         type=raw,value=nightly
-        type=schedule,pattern=${{ needs.compute-suffix.outputs.prerelease }}
+        type=raw,value=${{ needs.compute-suffix.outputs.prerelease }}
     secrets: inherit
diff --git a/Gemfile b/Gemfile
index cd0ef255b1..ad7f0b3d40 100644
--- a/Gemfile
+++ b/Gemfile
@@ -26,7 +26,7 @@ gem 'blurhash', '~> 0.1'
 
 gem 'active_model_serializers', '~> 0.10'
 gem 'addressable', '~> 2.8'
-gem 'bootsnap', '~> 1.17.0', require: false
+gem 'bootsnap', '~> 1.18.0', require: false
 gem 'browser'
 gem 'charlock_holmes', '~> 0.7.7'
 gem 'chewy', '~> 7.3'
@@ -63,7 +63,7 @@ gem 'kaminari', '~> 1.2'
 gem 'link_header', '~> 0.0'
 gem 'mime-types', '~> 3.5.0', require: 'mime/types/columnar'
 gem 'nokogiri', '~> 1.15'
-gem 'nsa', github: 'jhawthorn/nsa', ref: 'e020fcc3a54d993ab45b7194d89ab720296c111b'
+gem 'nsa'
 gem 'oj', '~> 3.14'
 gem 'ox', '~> 2.14'
 gem 'parslet'
diff --git a/Gemfile.lock b/Gemfile.lock
index 539db17e59..303c5c5079 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -7,17 +7,6 @@ GIT
       hkdf (~> 0.2)
       jwt (~> 2.0)
 
-GIT
-  remote: https://github.com/jhawthorn/nsa.git
-  revision: e020fcc3a54d993ab45b7194d89ab720296c111b
-  ref: e020fcc3a54d993ab45b7194d89ab720296c111b
-  specs:
-    nsa (0.2.8)
-      activesupport (>= 4.2, < 7.2)
-      concurrent-ruby (~> 1.0, >= 1.0.2)
-      sidekiq (>= 3.5)
-      statsd-ruby (~> 1.4, >= 1.4.0)
-
 GEM
   remote: https://rubygems.org/
   specs:
@@ -155,9 +144,9 @@ GEM
     binding_of_caller (1.0.0)
       debug_inspector (>= 0.0.1)
     blurhash (0.1.7)
-    bootsnap (1.17.1)
+    bootsnap (1.18.3)
       msgpack (~> 1.2)
-    brakeman (6.1.1)
+    brakeman (6.1.2)
       racc
     browser (5.3.1)
     brpoplpush-redis_script (0.1.3)
@@ -167,11 +156,11 @@ GEM
     bundler-audit (0.9.1)
       bundler (>= 1.2.0, < 3)
       thor (~> 1.0)
-    capybara (3.39.2)
+    capybara (3.40.0)
       addressable
       matrix
       mini_mime (>= 0.1.3)
-      nokogiri (~> 1.8)
+      nokogiri (~> 1.11)
       rack (>= 1.6.0)
       rack-test (>= 0.6.3)
       regexp_parser (>= 1.5, < 3.0)
@@ -180,7 +169,7 @@ GEM
       activesupport
     cbor (0.5.9.6)
     charlock_holmes (0.7.7)
-    chewy (7.5.0)
+    chewy (7.5.1)
       activesupport (>= 5.2)
       elasticsearch (>= 7.12.0, < 7.14.0)
       elasticsearch-dsl
@@ -319,7 +308,7 @@ GEM
       activesupport (>= 5.1)
       haml (>= 4.0.6)
       railties (>= 5.1)
-    haml_lint (0.55.0)
+    haml_lint (0.56.0)
       haml (>= 5.0)
       parallel (~> 1.10)
       rainbow
@@ -468,6 +457,11 @@ GEM
     nokogiri (1.16.2)
       mini_portile2 (~> 2.8.2)
       racc (~> 1.4)
+    nsa (0.3.0)
+      activesupport (>= 4.2, < 7.2)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      sidekiq (>= 3.5)
+      statsd-ruby (~> 1.4, >= 1.4.0)
     oj (3.16.3)
       bigdecimal (>= 3.0)
     omniauth (2.1.1)
@@ -510,7 +504,7 @@ GEM
     parslet (2.0.0)
     pastel (0.8.0)
       tty-color (~> 0.5)
-    pg (1.5.4)
+    pg (1.5.5)
     pghero (3.4.0)
       activerecord (>= 6)
     posix-spawn (0.3.15)
@@ -771,7 +765,7 @@ GEM
       unf (~> 0.1.0)
     tzinfo (2.0.6)
       concurrent-ruby (~> 1.0)
-    tzinfo-data (1.2023.4)
+    tzinfo-data (1.2024.1)
       tzinfo (>= 1.0.0)
     unf (0.1.4)
       unf_ext
@@ -829,7 +823,7 @@ DEPENDENCIES
   better_errors (~> 2.9)
   binding_of_caller (~> 1.0)
   blurhash (~> 0.1)
-  bootsnap (~> 1.17.0)
+  bootsnap (~> 1.18.0)
   brakeman (~> 6.0)
   browser
   bundler-audit (~> 0.9)
@@ -886,7 +880,7 @@ DEPENDENCIES
   net-http (~> 0.4.0)
   net-ldap (~> 0.18)
   nokogiri (~> 1.15)
-  nsa!
+  nsa
   oj (~> 3.14)
   omniauth (~> 2.0)
   omniauth-cas (~> 3.0.0.beta.1)
diff --git a/app/controllers/auth/omniauth_callbacks_controller.rb b/app/controllers/auth/omniauth_callbacks_controller.rb
index 9b83de945b..9d496220a3 100644
--- a/app/controllers/auth/omniauth_callbacks_controller.rb
+++ b/app/controllers/auth/omniauth_callbacks_controller.rb
@@ -17,6 +17,9 @@ class Auth::OmniauthCallbacksController < Devise::OmniauthCallbacksController
         session["devise.#{provider}_data"] = request.env['omniauth.auth']
         redirect_to new_user_registration_url
       end
+    rescue ActiveRecord::RecordInvalid
+      flash[:alert] = I18n.t('devise.failure.omniauth_user_creation_failure') if is_navigational_format?
+      redirect_to new_user_session_url
     end
   end
 
diff --git a/app/helpers/jsonld_helper.rb b/app/helpers/jsonld_helper.rb
index 1b840f566b..05de70970c 100644
--- a/app/helpers/jsonld_helper.rb
+++ b/app/helpers/jsonld_helper.rb
@@ -174,7 +174,19 @@ module JsonLdHelper
     build_request(uri, on_behalf_of).perform do |response|
       raise Mastodon::UnexpectedResponseError, response unless response_successful?(response) || response_error_unsalvageable?(response) || !raise_on_temporary_error
 
-      body_to_json(response.body_with_limit) if response.code == 200
+      body_to_json(response.body_with_limit) if response.code == 200 && valid_activitypub_content_type?(response)
+    end
+  end
+
+  def valid_activitypub_content_type?(response)
+    return true if response.mime_type == 'application/activity+json'
+
+    # When the mime type is `application/ld+json`, we need to check the profile,
+    # but `http.rb` does not parse it for us.
+    return false unless response.mime_type == 'application/ld+json'
+
+    response.headers[HTTP::Headers::CONTENT_TYPE]&.split(';')&.map(&:strip)&.any? do |str|
+      str.start_with?('profile="') && str[9...-1].split.include?('https://www.w3.org/ns/activitystreams')
     end
   end
 
diff --git a/app/javascript/flavours/glitch/features/hashtag_timeline/components/column_settings.jsx b/app/javascript/flavours/glitch/features/hashtag_timeline/components/column_settings.jsx
index c60de4c518..4488c5b2a0 100644
--- a/app/javascript/flavours/glitch/features/hashtag_timeline/components/column_settings.jsx
+++ b/app/javascript/flavours/glitch/features/hashtag_timeline/components/column_settings.jsx
@@ -9,6 +9,8 @@ import { NonceProvider } from 'react-select';
 import AsyncSelect from 'react-select/async';
 import Toggle from 'react-toggle';
 
+import { maxFeedHashtags } from 'flavours/glitch/initial_state';
+
 import SettingToggle from '../../notifications/components/setting_toggle';
 
 const messages = defineMessages({
@@ -46,9 +48,9 @@ class ColumnSettings extends PureComponent {
   onSelect = mode => value => {
     const oldValue = this.tags(mode);
 
-    // Prevent changes that add more than 4 tags, but allow removing
-    // tags that were already added before
-    if ((value.length > 4) && !(value < oldValue)) {
+    // Prevent changes that add more than the number of configured
+    // tags, but allow removing tags that were already added before
+    if ((value.length > maxFeedHashtags) && !(value < oldValue)) {
       return;
     }
 
diff --git a/app/javascript/flavours/glitch/features/ui/components/doodle_modal.jsx b/app/javascript/flavours/glitch/features/ui/components/doodle_modal.jsx
index d682ef161d..ba593fc9fc 100644
--- a/app/javascript/flavours/glitch/features/ui/components/doodle_modal.jsx
+++ b/app/javascript/flavours/glitch/features/ui/components/doodle_modal.jsx
@@ -9,6 +9,10 @@ import { connect } from 'react-redux';
 import Atrament from 'atrament'; // the doodling library
 import { debounce, mapValues } from 'lodash';
 
+import ColorsIcon from '@/material-icons/400-24px/colors.svg?react';
+import DeleteIcon from '@/material-icons/400-24px/delete.svg?react';
+import EditIcon from '@/material-icons/400-24px/edit.svg?react';
+import UndoIcon from '@/material-icons/400-24px/undo.svg?react';
 import { doodleSet, uploadCompose } from 'flavours/glitch/actions/compose';
 import { Button } from 'flavours/glitch/components/button';
 import { IconButton } from 'flavours/glitch/components/icon_button';
@@ -584,10 +588,10 @@ class DoodleModal extends ImmutablePureComponent {
             </div>
           </div>
           <div className='doodle-toolbar'>
-            <IconButton icon='pencil' title='Draw' label='Draw' onClick={this.setModeDraw} size={18} active={this.mode === 'draw'} inverted />
-            <IconButton icon='bath' title='Fill' label='Fill' onClick={this.setModeFill} size={18} active={this.mode === 'fill'} inverted />
-            <IconButton icon='undo' title='Undo' label='Undo' onClick={this.undo} size={18} inverted />
-            <IconButton icon='trash' title='Clear' label='Clear' onClick={this.handleClearBtn} size={18} inverted />
+            <IconButton icon='pencil' iconComponent={EditIcon} title='Draw' label='Draw' onClick={this.setModeDraw} size={18} active={this.mode === 'draw'} inverted />
+            <IconButton icon='bath' iconComponent={ColorsIcon} title='Fill' label='Fill' onClick={this.setModeFill} size={18} active={this.mode === 'fill'} inverted />
+            <IconButton icon='undo' iconComponent={UndoIcon} title='Undo' label='Undo' onClick={this.undo} size={18} inverted />
+            <IconButton icon='trash' iconComponent={DeleteIcon} title='Clear' label='Clear' onClick={this.handleClearBtn} size={18} inverted />
           </div>
           <div className='doodle-palette'>
             {
diff --git a/app/javascript/flavours/glitch/initial_state.js b/app/javascript/flavours/glitch/initial_state.js
index fabe0a72e1..a281dbaf31 100644
--- a/app/javascript/flavours/glitch/initial_state.js
+++ b/app/javascript/flavours/glitch/initial_state.js
@@ -67,6 +67,7 @@ export const hasMultiColumnPath = initialPath === '/'
  * @property {InitialStateMeta} meta
  * @property {object} local_settings
  * @property {number} max_toot_chars
+ * @property {number} max_feed_hashtags
  * @property {number} poll_limits
  */
 
@@ -130,6 +131,7 @@ export const sso_redirect = getMeta('sso_redirect');
 
 // Glitch-soc-specific settings
 export const maxChars = (initialState && initialState.max_toot_chars) || 500;
+export const maxFeedHashtags = (initialState && initialState.max_feed_hashtags) || 4;
 export const favouriteModal = getMeta('favourite_modal');
 export const pollLimits = (initialState && initialState.poll_limits);
 export const defaultContentType = getMeta('default_content_type');
diff --git a/app/javascript/flavours/glitch/locales/id.json b/app/javascript/flavours/glitch/locales/id.json
index d360fed722..f37788bc80 100644
--- a/app/javascript/flavours/glitch/locales/id.json
+++ b/app/javascript/flavours/glitch/locales/id.json
@@ -1,4 +1,51 @@
 {
+  "about.fork_disclaimer": "Glitch-soc adalah perangkat lunak sumber terbuka yang merupakan fork dari Mastodon.",
+  "account.disclaimer_full": "Informasi di bawah ini mungkin tidak mencerminkan profil pengguna secara lengkap.",
+  "account.follows": "Mengikuti",
+  "account.joined": "Bergabung {date}",
+  "account.suspended_disclaimer_full": "Pengguna ini telah ditangguhkan oleh moderator.",
+  "account.view_full_profile": "Tampilkan profil lengkap",
+  "advanced_options.icon_title": "Opsi lanjutan",
+  "advanced_options.local-only.long": "Jangan mengunggah ke instance lain",
+  "advanced_options.local-only.short": "Hanya lokal",
+  "advanced_options.local-only.tooltip": "Postingan ini hanya untuk lokal",
+  "advanced_options.threaded_mode.long": "Secara otomatis membuka balasan pada postingan",
+  "advanced_options.threaded_mode.short": "Mode Utasan",
+  "advanced_options.threaded_mode.tooltip": "Mode utasan dinyalakan",
+  "boost_modal.missing_description": "Toot ini berisi beberapa media tanpa deskripsi",
+  "column.favourited_by": "Disukai oleh",
+  "column.heading": "Lainnya",
+  "column.reblogged_by": "Dibagikan oleh",
+  "column.subheading": "Opsi lain-lain",
+  "column_header.profile": "Profil",
+  "column_subheading.lists": "Daftar",
+  "column_subheading.navigation": "Penelusuran",
+  "community.column_settings.allow_local_only": "Tampilkan toot lokal saja",
+  "compose.attach": "Lampirkan...",
+  "compose.attach.doodle": "Gambar sesuatu",
+  "compose.attach.upload": "Unggah file",
+  "compose.content-type.html": "HTML",
+  "compose.content-type.markdown": "Bahasa Markdown",
+  "compose.content-type.plain": "Teks biasa",
+  "compose_form.poll.multiple_choices": "Izinkan beberapa pilihan",
+  "compose_form.poll.single_choice": "Izinkan hanya satu pilihan",
+  "compose_form.spoiler": "Sembunyikan teks di balik peringatan",
+  "confirmation_modal.do_not_ask_again": "Jangan minta konfirmasi lagi",
+  "confirmations.deprecated_settings.confirm": "Gunakan preferensi Mastodon",
+  "confirmations.deprecated_settings.message": "Beberapa {app_settings} khusus perangkat Glitch-soc yang Anda gunakan telah digantikan oleh {preferences} Mastodon dan akan diganti:",
+  "confirmations.missing_media_description.confirm": "Tetap kirim",
+  "confirmations.missing_media_description.edit": "Sunting media",
+  "confirmations.missing_media_description.message": "Setidaknya satu lampiran media tidak memiliki deskripsi. Pertimbangkan untuk mendeskripsikan semua lampiran media untuk pengguna tunanetra sebelum mengirim toot Anda.",
+  "confirmations.unfilter.author": "Penulis",
+  "confirmations.unfilter.confirm": "Tampilkan",
+  "confirmations.unfilter.edit_filter": "Ubah saringan",
+  "content-type.change": "Jenis konten",
+  "direct.group_by_conversations": "Grupkan berdasarkan percakapan",
+  "endorsed_accounts_editor.endorsed_accounts": "Akun pilihan",
+  "favourite_modal.combo": "Anda dapat menekan {combo} untuk melewati ini lain kali",
+  "firehose.column_settings.allow_local_only": "Tampilkan postingan khusus lokal di \"Semua\"",
+  "home.column_settings.advanced": "Lanjutan",
+  "home.column_settings.filter_regex": "Saring dengan ekspresi reguler",
   "settings.content_warnings": "Content warnings",
   "settings.preferences": "Preferences"
 }
diff --git a/app/javascript/flavours/glitch/locales/sv.json b/app/javascript/flavours/glitch/locales/sv.json
index d360fed722..3212f7ff88 100644
--- a/app/javascript/flavours/glitch/locales/sv.json
+++ b/app/javascript/flavours/glitch/locales/sv.json
@@ -1,4 +1,52 @@
 {
+  "account.follows": "Följer",
+  "account.joined": "Gick med {date}",
+  "account.suspended_disclaimer_full": "Denna användare har stängts av av en moderator.",
+  "account.view_full_profile": "Visa full profil",
+  "advanced_options.icon_title": "Avancerade inställningar",
+  "advanced_options.local-only.long": "Lägg inte ut på andra instanser",
+  "advanced_options.local-only.short": "Endast lokalt",
+  "advanced_options.local-only.tooltip": "Detta inlägg är endast tillgängligt lokalt",
+  "advanced_options.threaded_mode.long": "Öppnar automatiskt ett svar vid publicering",
+  "advanced_options.threaded_mode.short": "Tråd-läge",
+  "advanced_options.threaded_mode.tooltip": "Tråd-läge på",
+  "boost_modal.missing_description": "Denna toot innehåller viss media utan beskrivning",
+  "column.favourited_by": "Favoritmarkerad av",
+  "column.heading": "Övrigt",
+  "column.reblogged_by": "Boostad av",
+  "column.subheading": "Övriga val",
+  "column_header.profile": "Profil",
+  "column_subheading.lists": "Listor",
+  "column_subheading.navigation": "Navigering",
+  "community.column_settings.allow_local_only": "Visa endast lokala toots",
+  "compose.attach": "Bifoga...",
+  "compose.attach.doodle": "Rita något",
+  "compose.attach.upload": "Ladda upp en fil",
+  "compose.content-type.html": "HTML",
+  "compose.content-type.markdown": "Markdown",
+  "compose.content-type.plain": "Klartext",
+  "compose_form.poll.multiple_choices": "Tillåt flera val",
+  "compose_form.poll.single_choice": "Tillåt ett val",
+  "compose_form.spoiler": "Göm text bakom varning",
+  "confirmation_modal.do_not_ask_again": "Fråga mig inte igen",
+  "confirmations.deprecated_settings.confirm": "Använd Mastodon-preferenser",
+  "confirmations.deprecated_settings.message": "Några av de glitch-soc-enhetsspecifika {app_settings} som du använder har ersatts av Mastodon-{preferences} och kommer att åsidosättas:",
+  "confirmations.missing_media_description.confirm": "Lägg ut ändå",
+  "confirmations.missing_media_description.edit": "Redigera media",
+  "confirmations.missing_media_description.message": "Minst en mediebilaga saknar beskrivning. Överväg att beskriva all media för synskadade innan du skickar din toot.",
+  "confirmations.unfilter.author": "Användare",
+  "confirmations.unfilter.confirm": "Visa",
+  "confirmations.unfilter.edit_filter": "Redigera filter",
+  "confirmations.unfilter.filters": "Matchande {count, plural, one {filter} other {filters}}",
+  "content-type.change": "Innehållstyp",
+  "direct.group_by_conversations": "Sortera efter konversation",
+  "endorsed_accounts_editor.endorsed_accounts": "Utvalda konton",
+  "favourite_modal.combo": "Du kan trycka på {combo} för att skippa detta nästa gång",
+  "firehose.column_settings.allow_local_only": "Visa endast lokala inlägg i \"Alla\"",
+  "home.column_settings.advanced": "Avancerat",
+  "home.column_settings.filter_regex": "Filtrera bort med reguljära uttryck",
+  "home.column_settings.show_direct": "Visa privata omnämningar",
+  "home.settings": "Kolumninställningar",
   "settings.content_warnings": "Content warnings",
   "settings.preferences": "Preferences"
 }
diff --git a/app/javascript/material-icons/400-24px/colors-fill.svg b/app/javascript/material-icons/400-24px/colors-fill.svg
new file mode 100644
index 0000000000..5e4b534fe2
--- /dev/null
+++ b/app/javascript/material-icons/400-24px/colors-fill.svg
@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" height="24" viewBox="0 -960 960 960" width="24"><path d="M346-140 100-386q-10-10-15-22t-5-25q0-13 5-25t15-22l230-229-106-106 62-65 400 400q10 10 14.5 22t4.5 25q0 13-4.5 25T686-386L440-140q-10 10-22 15t-25 5q-13 0-25-5t-22-15Zm47-506L179-432h428L393-646Zm399 526q-36 0-61-25.5T706-208q0-27 13.5-51t30.5-47l42-54 44 54q16 23 30 47t14 51q0 37-26 62.5T792-120Z"/></svg>
\ No newline at end of file
diff --git a/app/javascript/material-icons/400-24px/colors.svg b/app/javascript/material-icons/400-24px/colors.svg
new file mode 100644
index 0000000000..5e4b534fe2
--- /dev/null
+++ b/app/javascript/material-icons/400-24px/colors.svg
@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" height="24" viewBox="0 -960 960 960" width="24"><path d="M346-140 100-386q-10-10-15-22t-5-25q0-13 5-25t15-22l230-229-106-106 62-65 400 400q10 10 14.5 22t4.5 25q0 13-4.5 25T686-386L440-140q-10 10-22 15t-25 5q-13 0-25-5t-22-15Zm47-506L179-432h428L393-646Zm399 526q-36 0-61-25.5T706-208q0-27 13.5-51t30.5-47l42-54 44 54q16 23 30 47t14 51q0 37-26 62.5T792-120Z"/></svg>
\ No newline at end of file
diff --git a/app/javascript/material-icons/400-24px/undo-fill.svg b/app/javascript/material-icons/400-24px/undo-fill.svg
new file mode 100644
index 0000000000..c451e1adc7
--- /dev/null
+++ b/app/javascript/material-icons/400-24px/undo-fill.svg
@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" height="24" viewBox="0 -960 960 960" width="24"><path d="M280-200v-80h284q63 0 109.5-40T720-420q0-60-46.5-100T564-560H312l104 104-56 56-200-200 200-200 56 56-104 104h252q97 0 166.5 63T800-420q0 94-69.5 157T564-200H280Z"/></svg>
\ No newline at end of file
diff --git a/app/javascript/material-icons/400-24px/undo.svg b/app/javascript/material-icons/400-24px/undo.svg
new file mode 100644
index 0000000000..c451e1adc7
--- /dev/null
+++ b/app/javascript/material-icons/400-24px/undo.svg
@@ -0,0 +1 @@
+<svg xmlns="http://www.w3.org/2000/svg" height="24" viewBox="0 -960 960 960" width="24"><path d="M280-200v-80h284q63 0 109.5-40T720-420q0-60-46.5-100T564-560H312l104 104-56 56-200-200 200-200 56 56-104 104h252q97 0 166.5 63T800-420q0 94-69.5 157T564-200H280Z"/></svg>
\ No newline at end of file
diff --git a/app/models/tag_feed.rb b/app/models/tag_feed.rb
index fbbdbaae27..051b0d1306 100644
--- a/app/models/tag_feed.rb
+++ b/app/models/tag_feed.rb
@@ -1,7 +1,7 @@
 # frozen_string_literal: true
 
 class TagFeed < PublicFeed
-  LIMIT_PER_MODE = 4
+  LIMIT_PER_MODE = (ENV['MAX_FEED_HASHTAGS'] || 4).to_i
 
   # @param [Tag] tag
   # @param [Account] account
diff --git a/app/serializers/initial_state_serializer.rb b/app/serializers/initial_state_serializer.rb
index ee79c38195..4135d8ed39 100644
--- a/app/serializers/initial_state_serializer.rb
+++ b/app/serializers/initial_state_serializer.rb
@@ -5,7 +5,7 @@ class InitialStateSerializer < ActiveModel::Serializer
 
   attributes :meta, :compose, :accounts,
              :media_attachments, :settings,
-             :max_toot_chars, :poll_limits,
+             :max_toot_chars, :max_feed_hashtags, :poll_limits,
              :languages
 
   attribute :critical_updates_pending, if: -> { object&.role&.can?(:view_devops) && SoftwareUpdate.check_enabled? }
@@ -17,6 +17,10 @@ class InitialStateSerializer < ActiveModel::Serializer
     StatusLengthValidator::MAX_CHARS
   end
 
+  def max_feed_hashtags
+    TagFeed::LIMIT_PER_MODE
+  end
+
   def poll_limits
     {
       max_options: PollValidator::MAX_OPTIONS,
diff --git a/app/services/fetch_resource_service.rb b/app/services/fetch_resource_service.rb
index 71c6cca790..84c36f6a10 100644
--- a/app/services/fetch_resource_service.rb
+++ b/app/services/fetch_resource_service.rb
@@ -44,7 +44,7 @@ class FetchResourceService < BaseService
     @response_code = response.code
     return nil if response.code != 200
 
-    if ['application/activity+json', 'application/ld+json'].include?(response.mime_type)
+    if valid_activitypub_content_type?(response)
       body = response.body_with_limit
       json = body_to_json(body)
 
diff --git a/app/views/user_mailer/confirmation_instructions.html.haml b/app/views/user_mailer/confirmation_instructions.html.haml
index 74b2d49a47..13e68c722b 100644
--- a/app/views/user_mailer/confirmation_instructions.html.haml
+++ b/app/views/user_mailer/confirmation_instructions.html.haml
@@ -8,9 +8,7 @@
           %td.email-inner-card-td.email-prose
             %p= t @resource.approved? ? 'devise.mailer.confirmation_instructions.explanation' : 'devise.mailer.confirmation_instructions.explanation_when_pending', host: site_hostname
             - if @resource.created_by_application
-              = render 'application/mailer/button', text: t('settings.account_settings'), url: edit_user_registration_url
-              = link_to confirmation_url(@resource, confirmation_token: @token, redirect_to_app: 'true') do
-                %span= t 'devise.mailer.confirmation_instructions.action_with_app', app: @resource.created_by_application.name
+              = render 'application/mailer/button', text: t('devise.mailer.confirmation_instructions.action_with_app', app: @resource.created_by_application.name), url: confirmation_url(@resource, confirmation_token: @token, redirect_to_app: 'true')
             - else
               = render 'application/mailer/button', text: t('devise.mailer.confirmation_instructions.action'), url: confirmation_url(@resource, confirmation_token: @token)
             %p= t 'devise.mailer.confirmation_instructions.extra_html', terms_path: about_more_url, policy_path: privacy_policy_url
diff --git a/config/initializers/sidekiq.rb b/config/initializers/sidekiq.rb
index 9a2743ed5b..53b02edc40 100644
--- a/config/initializers/sidekiq.rb
+++ b/config/initializers/sidekiq.rb
@@ -26,6 +26,7 @@ Sidekiq.configure_server do |config|
           'queue' => 'scheduler',
         },
       }
+      SidekiqScheduler::Scheduler.instance.reload_schedule!
     end
   end
 
diff --git a/config/locales/devise.en.yml b/config/locales/devise.en.yml
index 4439397c8e..61bd33851b 100644
--- a/config/locales/devise.en.yml
+++ b/config/locales/devise.en.yml
@@ -12,6 +12,7 @@ en:
       last_attempt: You have one more attempt before your account is locked.
       locked: Your account is locked.
       not_found_in_database: Invalid %{authentication_keys} or password.
+      omniauth_user_creation_failure: Error creating an account for this identity.
       pending: Your account is still under review.
       timeout: Your session expired. Please login again to continue.
       unauthenticated: You need to login or sign up before continuing.
diff --git a/spec/helpers/json_ld_helper_spec.rb b/spec/helpers/json_ld_helper_spec.rb
index 99857278a1..4855085027 100644
--- a/spec/helpers/json_ld_helper_spec.rb
+++ b/spec/helpers/json_ld_helper_spec.rb
@@ -56,15 +56,15 @@ describe JsonLdHelper do
   describe '#fetch_resource' do
     context 'when the second argument is false' do
       it 'returns resource even if the retrieved ID and the given URI does not match' do
-        stub_request(:get, 'https://bob.test/').to_return body: '{"id": "https://alice.test/"}'
-        stub_request(:get, 'https://alice.test/').to_return body: '{"id": "https://alice.test/"}'
+        stub_request(:get, 'https://bob.test/').to_return(body: '{"id": "https://alice.test/"}', headers: { 'Content-Type': 'application/activity+json' })
+        stub_request(:get, 'https://alice.test/').to_return(body: '{"id": "https://alice.test/"}', headers: { 'Content-Type': 'application/activity+json' })
 
         expect(fetch_resource('https://bob.test/', false)).to eq({ 'id' => 'https://alice.test/' })
       end
 
       it 'returns nil if the object identified by the given URI and the object identified by the retrieved ID does not match' do
-        stub_request(:get, 'https://mallory.test/').to_return body: '{"id": "https://marvin.test/"}'
-        stub_request(:get, 'https://marvin.test/').to_return body: '{"id": "https://alice.test/"}'
+        stub_request(:get, 'https://mallory.test/').to_return(body: '{"id": "https://marvin.test/"}', headers: { 'Content-Type': 'application/activity+json' })
+        stub_request(:get, 'https://marvin.test/').to_return(body: '{"id": "https://alice.test/"}', headers: { 'Content-Type': 'application/activity+json' })
 
         expect(fetch_resource('https://mallory.test/', false)).to be_nil
       end
@@ -72,7 +72,7 @@ describe JsonLdHelper do
 
     context 'when the second argument is true' do
       it 'returns nil if the retrieved ID and the given URI does not match' do
-        stub_request(:get, 'https://mallory.test/').to_return body: '{"id": "https://alice.test/"}'
+        stub_request(:get, 'https://mallory.test/').to_return(body: '{"id": "https://alice.test/"}', headers: { 'Content-Type': 'application/activity+json' })
         expect(fetch_resource('https://mallory.test/', true)).to be_nil
       end
     end
@@ -80,12 +80,12 @@ describe JsonLdHelper do
 
   describe '#fetch_resource_without_id_validation' do
     it 'returns nil if the status code is not 200' do
-      stub_request(:get, 'https://host.test/').to_return status: 400, body: '{}'
+      stub_request(:get, 'https://host.test/').to_return(status: 400, body: '{}', headers: { 'Content-Type': 'application/activity+json' })
       expect(fetch_resource_without_id_validation('https://host.test/')).to be_nil
     end
 
     it 'returns hash' do
-      stub_request(:get, 'https://host.test/').to_return status: 200, body: '{}'
+      stub_request(:get, 'https://host.test/').to_return(status: 200, body: '{}', headers: { 'Content-Type': 'application/activity+json' })
       expect(fetch_resource_without_id_validation('https://host.test/')).to eq({})
     end
   end
diff --git a/spec/lib/activitypub/activity/announce_spec.rb b/spec/lib/activitypub/activity/announce_spec.rb
index 8ad892975d..b556bfd6c2 100644
--- a/spec/lib/activitypub/activity/announce_spec.rb
+++ b/spec/lib/activitypub/activity/announce_spec.rb
@@ -35,7 +35,7 @@ RSpec.describe ActivityPub::Activity::Announce do
     context 'when sender is followed by a local account' do
       before do
         Fabricate(:account).follow!(sender)
-        stub_request(:get, 'https://example.com/actor/hello-world').to_return(body: Oj.dump(unknown_object_json))
+        stub_request(:get, 'https://example.com/actor/hello-world').to_return(body: Oj.dump(unknown_object_json), headers: { 'Content-Type': 'application/activity+json' })
         subject.perform
       end
 
@@ -120,7 +120,7 @@ RSpec.describe ActivityPub::Activity::Announce do
       let(:object_json) { 'https://example.com/actor/hello-world' }
 
       before do
-        stub_request(:get, 'https://example.com/actor/hello-world').to_return(body: Oj.dump(unknown_object_json))
+        stub_request(:get, 'https://example.com/actor/hello-world').to_return(body: Oj.dump(unknown_object_json), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       context 'when the relay is enabled' do
diff --git a/spec/requests/omniauth_callbacks_spec.rb b/spec/requests/omniauth_callbacks_spec.rb
index 1e488b3f43..095535e485 100644
--- a/spec/requests/omniauth_callbacks_spec.rb
+++ b/spec/requests/omniauth_callbacks_spec.rb
@@ -60,11 +60,13 @@ describe 'OmniAuth callbacks' do
         end
 
         context 'when ALLOW_UNSAFE_AUTH_PROVIDER_REATTACH is not set to true' do
-          it 'does not match the existing user or create an identity' do
+          it 'does not match the existing user or create an identity, and redirects to login page' do
             expect { subject }
               .to not_change(User, :count)
               .and not_change(Identity, :count)
               .and not_change(LoginActivity, :count)
+
+            expect(response).to redirect_to(new_user_session_url)
           end
         end
       end
diff --git a/spec/services/activitypub/fetch_featured_collection_service_spec.rb b/spec/services/activitypub/fetch_featured_collection_service_spec.rb
index b9e95b825f..dab204406b 100644
--- a/spec/services/activitypub/fetch_featured_collection_service_spec.rb
+++ b/spec/services/activitypub/fetch_featured_collection_service_spec.rb
@@ -72,11 +72,11 @@ RSpec.describe ActivityPub::FetchFeaturedCollectionService, type: :service do
 
   shared_examples 'sets pinned posts' do
     before do
-      stub_request(:get, 'https://example.com/account/pinned/known').to_return(status: 200, body: Oj.dump(status_json_pinned_known))
-      stub_request(:get, 'https://example.com/account/pinned/unknown-inlined').to_return(status: 200, body: Oj.dump(status_json_pinned_unknown_inlined))
+      stub_request(:get, 'https://example.com/account/pinned/known').to_return(status: 200, body: Oj.dump(status_json_pinned_known), headers: { 'Content-Type': 'application/activity+json' })
+      stub_request(:get, 'https://example.com/account/pinned/unknown-inlined').to_return(status: 200, body: Oj.dump(status_json_pinned_unknown_inlined), headers: { 'Content-Type': 'application/activity+json' })
       stub_request(:get, 'https://example.com/account/pinned/unknown-unreachable').to_return(status: 404)
-      stub_request(:get, 'https://example.com/account/pinned/unknown-reachable').to_return(status: 200, body: Oj.dump(status_json_pinned_unknown_reachable))
-      stub_request(:get, 'https://example.com/account/collections/featured').to_return(status: 200, body: Oj.dump(featured_with_null))
+      stub_request(:get, 'https://example.com/account/pinned/unknown-reachable').to_return(status: 200, body: Oj.dump(status_json_pinned_unknown_reachable), headers: { 'Content-Type': 'application/activity+json' })
+      stub_request(:get, 'https://example.com/account/collections/featured').to_return(status: 200, body: Oj.dump(featured_with_null), headers: { 'Content-Type': 'application/activity+json' })
 
       subject.call(actor, note: true, hashtag: false)
     end
@@ -94,7 +94,7 @@ RSpec.describe ActivityPub::FetchFeaturedCollectionService, type: :service do
   describe '#call' do
     context 'when the endpoint is a Collection' do
       before do
-        stub_request(:get, actor.featured_collection_url).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, actor.featured_collection_url).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'sets pinned posts'
@@ -111,7 +111,7 @@ RSpec.describe ActivityPub::FetchFeaturedCollectionService, type: :service do
       end
 
       before do
-        stub_request(:get, actor.featured_collection_url).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, actor.featured_collection_url).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'sets pinned posts'
@@ -120,7 +120,7 @@ RSpec.describe ActivityPub::FetchFeaturedCollectionService, type: :service do
         let(:items) { 'https://example.com/account/pinned/unknown-reachable' }
 
         before do
-          stub_request(:get, 'https://example.com/account/pinned/unknown-reachable').to_return(status: 200, body: Oj.dump(status_json_pinned_unknown_reachable))
+          stub_request(:get, 'https://example.com/account/pinned/unknown-reachable').to_return(status: 200, body: Oj.dump(status_json_pinned_unknown_reachable), headers: { 'Content-Type': 'application/activity+json' })
           subject.call(actor, note: true, hashtag: false)
         end
 
@@ -147,7 +147,7 @@ RSpec.describe ActivityPub::FetchFeaturedCollectionService, type: :service do
       end
 
       before do
-        stub_request(:get, actor.featured_collection_url).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, actor.featured_collection_url).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'sets pinned posts'
@@ -156,7 +156,7 @@ RSpec.describe ActivityPub::FetchFeaturedCollectionService, type: :service do
         let(:items) { 'https://example.com/account/pinned/unknown-reachable' }
 
         before do
-          stub_request(:get, 'https://example.com/account/pinned/unknown-reachable').to_return(status: 200, body: Oj.dump(status_json_pinned_unknown_reachable))
+          stub_request(:get, 'https://example.com/account/pinned/unknown-reachable').to_return(status: 200, body: Oj.dump(status_json_pinned_unknown_reachable), headers: { 'Content-Type': 'application/activity+json' })
           subject.call(actor, note: true, hashtag: false)
         end
 
diff --git a/spec/services/activitypub/fetch_featured_tags_collection_service_spec.rb b/spec/services/activitypub/fetch_featured_tags_collection_service_spec.rb
index 071e4d92d5..638278a10e 100644
--- a/spec/services/activitypub/fetch_featured_tags_collection_service_spec.rb
+++ b/spec/services/activitypub/fetch_featured_tags_collection_service_spec.rb
@@ -38,7 +38,7 @@ RSpec.describe ActivityPub::FetchFeaturedTagsCollectionService, type: :service d
   describe '#call' do
     context 'when the endpoint is a Collection' do
       before do
-        stub_request(:get, collection_url).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, collection_url).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'sets featured tags'
@@ -46,7 +46,7 @@ RSpec.describe ActivityPub::FetchFeaturedTagsCollectionService, type: :service d
 
     context 'when the account already has featured tags' do
       before do
-        stub_request(:get, collection_url).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, collection_url).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
 
         actor.featured_tags.create!(name: 'FoO')
         actor.featured_tags.create!(name: 'baz')
@@ -67,7 +67,7 @@ RSpec.describe ActivityPub::FetchFeaturedTagsCollectionService, type: :service d
       end
 
       before do
-        stub_request(:get, collection_url).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, collection_url).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'sets featured tags'
@@ -88,7 +88,7 @@ RSpec.describe ActivityPub::FetchFeaturedTagsCollectionService, type: :service d
       end
 
       before do
-        stub_request(:get, collection_url).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, collection_url).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'sets featured tags'
diff --git a/spec/services/activitypub/fetch_remote_account_service_spec.rb b/spec/services/activitypub/fetch_remote_account_service_spec.rb
index f33a928da6..42badde051 100644
--- a/spec/services/activitypub/fetch_remote_account_service_spec.rb
+++ b/spec/services/activitypub/fetch_remote_account_service_spec.rb
@@ -44,7 +44,7 @@ RSpec.describe ActivityPub::FetchRemoteAccountService, type: :service do
       before do
         actor[:inbox] = nil
 
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
 
@@ -67,7 +67,7 @@ RSpec.describe ActivityPub::FetchRemoteAccountService, type: :service do
       let!(:webfinger) { { subject: 'acct:alice@example.com', links: [{ rel: 'self', href: 'https://example.com/alice' }] } }
 
       before do
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
 
@@ -93,7 +93,7 @@ RSpec.describe ActivityPub::FetchRemoteAccountService, type: :service do
       let!(:webfinger) { { subject: 'acct:alice@iscool.af', links: [{ rel: 'self', href: 'https://example.com/alice' }] } }
 
       before do
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
         stub_request(:get, 'https://iscool.af/.well-known/webfinger?resource=acct:alice@iscool.af').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
@@ -125,7 +125,7 @@ RSpec.describe ActivityPub::FetchRemoteAccountService, type: :service do
       let!(:webfinger) { { subject: 'acct:alice@example.com', links: [{ rel: 'self', href: 'https://example.com/bob' }] } }
 
       before do
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
 
@@ -148,7 +148,7 @@ RSpec.describe ActivityPub::FetchRemoteAccountService, type: :service do
       let!(:webfinger) { { subject: 'acct:alice@iscool.af', links: [{ rel: 'self', href: 'https://example.com/bob' }] } }
 
       before do
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
         stub_request(:get, 'https://iscool.af/.well-known/webfinger?resource=acct:alice@iscool.af').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
diff --git a/spec/services/activitypub/fetch_remote_actor_service_spec.rb b/spec/services/activitypub/fetch_remote_actor_service_spec.rb
index 944a2f8b1c..6d264b7b82 100644
--- a/spec/services/activitypub/fetch_remote_actor_service_spec.rb
+++ b/spec/services/activitypub/fetch_remote_actor_service_spec.rb
@@ -44,7 +44,7 @@ RSpec.describe ActivityPub::FetchRemoteActorService, type: :service do
       before do
         actor[:inbox] = nil
 
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
 
@@ -67,7 +67,7 @@ RSpec.describe ActivityPub::FetchRemoteActorService, type: :service do
       let!(:webfinger) { { subject: 'acct:alice@example.com', links: [{ rel: 'self', href: 'https://example.com/alice' }] } }
 
       before do
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
 
@@ -93,7 +93,7 @@ RSpec.describe ActivityPub::FetchRemoteActorService, type: :service do
       let!(:webfinger) { { subject: 'acct:alice@iscool.af', links: [{ rel: 'self', href: 'https://example.com/alice' }] } }
 
       before do
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
         stub_request(:get, 'https://iscool.af/.well-known/webfinger?resource=acct:alice@iscool.af').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
@@ -125,7 +125,7 @@ RSpec.describe ActivityPub::FetchRemoteActorService, type: :service do
       let!(:webfinger) { { subject: 'acct:alice@example.com', links: [{ rel: 'self', href: 'https://example.com/bob' }] } }
 
       before do
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
 
@@ -148,7 +148,7 @@ RSpec.describe ActivityPub::FetchRemoteActorService, type: :service do
       let!(:webfinger) { { subject: 'acct:alice@iscool.af', links: [{ rel: 'self', href: 'https://example.com/bob' }] } }
 
       before do
-        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+        stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
         stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
         stub_request(:get, 'https://iscool.af/.well-known/webfinger?resource=acct:alice@iscool.af').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
       end
diff --git a/spec/services/activitypub/fetch_remote_key_service_spec.rb b/spec/services/activitypub/fetch_remote_key_service_spec.rb
index 0b14da4f44..478778cc9f 100644
--- a/spec/services/activitypub/fetch_remote_key_service_spec.rb
+++ b/spec/services/activitypub/fetch_remote_key_service_spec.rb
@@ -50,7 +50,7 @@ RSpec.describe ActivityPub::FetchRemoteKeyService, type: :service do
   end
 
   before do
-    stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor))
+    stub_request(:get, 'https://example.com/alice').to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
     stub_request(:get, 'https://example.com/.well-known/webfinger?resource=acct:alice@example.com').to_return(body: Oj.dump(webfinger), headers: { 'Content-Type': 'application/jrd+json' })
   end
 
@@ -59,7 +59,7 @@ RSpec.describe ActivityPub::FetchRemoteKeyService, type: :service do
 
     context 'when the key is a sub-object from the actor' do
       before do
-        stub_request(:get, public_key_id).to_return(body: Oj.dump(actor))
+        stub_request(:get, public_key_id).to_return(body: Oj.dump(actor), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it 'returns the expected account' do
@@ -71,7 +71,7 @@ RSpec.describe ActivityPub::FetchRemoteKeyService, type: :service do
       let(:public_key_id) { 'https://example.com/alice-public-key.json' }
 
       before do
-        stub_request(:get, public_key_id).to_return(body: Oj.dump(key_json.merge({ '@context': ['https://www.w3.org/ns/activitystreams', 'https://w3id.org/security/v1'] })))
+        stub_request(:get, public_key_id).to_return(body: Oj.dump(key_json.merge({ '@context': ['https://www.w3.org/ns/activitystreams', 'https://w3id.org/security/v1'] })), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it 'returns the expected account' do
@@ -84,7 +84,7 @@ RSpec.describe ActivityPub::FetchRemoteKeyService, type: :service do
       let(:actor_public_key) { 'https://example.com/alice-public-key.json' }
 
       before do
-        stub_request(:get, public_key_id).to_return(body: Oj.dump(key_json.merge({ '@context': ['https://www.w3.org/ns/activitystreams', 'https://w3id.org/security/v1'] })))
+        stub_request(:get, public_key_id).to_return(body: Oj.dump(key_json.merge({ '@context': ['https://www.w3.org/ns/activitystreams', 'https://w3id.org/security/v1'] })), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it 'returns the nil' do
diff --git a/spec/services/activitypub/fetch_replies_service_spec.rb b/spec/services/activitypub/fetch_replies_service_spec.rb
index a76b996c20..8e1f606e26 100644
--- a/spec/services/activitypub/fetch_replies_service_spec.rb
+++ b/spec/services/activitypub/fetch_replies_service_spec.rb
@@ -58,7 +58,7 @@ RSpec.describe ActivityPub::FetchRepliesService, type: :service do
 
       context 'when passing the URL to the collection' do
         before do
-          stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload))
+          stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
         end
 
         it 'spawns workers for up to 5 replies on the same server' do
@@ -93,7 +93,7 @@ RSpec.describe ActivityPub::FetchRepliesService, type: :service do
 
       context 'when passing the URL to the collection' do
         before do
-          stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload))
+          stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
         end
 
         it 'spawns workers for up to 5 replies on the same server' do
@@ -132,7 +132,7 @@ RSpec.describe ActivityPub::FetchRepliesService, type: :service do
 
       context 'when passing the URL to the collection' do
         before do
-          stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload))
+          stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
         end
 
         it 'spawns workers for up to 5 replies on the same server' do
diff --git a/spec/services/activitypub/synchronize_followers_service_spec.rb b/spec/services/activitypub/synchronize_followers_service_spec.rb
index c9a513e24b..f62376ab95 100644
--- a/spec/services/activitypub/synchronize_followers_service_spec.rb
+++ b/spec/services/activitypub/synchronize_followers_service_spec.rb
@@ -60,7 +60,7 @@ RSpec.describe ActivityPub::SynchronizeFollowersService, type: :service do
   describe '#call' do
     context 'when the endpoint is a Collection of actor URIs' do
       before do
-        stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'synchronizes followers'
@@ -77,7 +77,7 @@ RSpec.describe ActivityPub::SynchronizeFollowersService, type: :service do
       end
 
       before do
-        stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'synchronizes followers'
@@ -98,7 +98,7 @@ RSpec.describe ActivityPub::SynchronizeFollowersService, type: :service do
       end
 
       before do
-        stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload))
+        stub_request(:get, collection_uri).to_return(status: 200, body: Oj.dump(payload), headers: { 'Content-Type': 'application/activity+json' })
       end
 
       it_behaves_like 'synchronizes followers'
diff --git a/spec/workers/activitypub/fetch_replies_worker_spec.rb b/spec/workers/activitypub/fetch_replies_worker_spec.rb
index ff4d049a26..2d080e286e 100644
--- a/spec/workers/activitypub/fetch_replies_worker_spec.rb
+++ b/spec/workers/activitypub/fetch_replies_worker_spec.rb
@@ -21,7 +21,7 @@ describe ActivityPub::FetchRepliesWorker do
 
   describe 'perform' do
     it 'performs a request if the collection URI is from the same host' do
-      stub_request(:get, 'https://example.com/statuses_replies/1').to_return(status: 200, body: json)
+      stub_request(:get, 'https://example.com/statuses_replies/1').to_return(status: 200, body: json, headers: { 'Content-Type': 'application/activity+json' })
       subject.perform(status.id, 'https://example.com/statuses_replies/1')
       expect(a_request(:get, 'https://example.com/statuses_replies/1')).to have_been_made.once
     end