diff --git a/.gitignore b/.gitignore
index 599b52b9e..6ae21e914 100644
--- a/.gitignore
+++ b/.gitignore
@@ -27,6 +27,8 @@ erl_crash.dump
 # variables.
 /config/*.secret.exs
 /config/generated_config.exs
+/config/*.env
+
 
 # Database setup file, some may forget to delete it
 /config/setup_db.psql
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 95f318584..7d5256600 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -67,6 +67,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Support pagination in emoji packs API (for packs and for files in pack)
 - Support for viewing instances favicons next to posts and accounts
 - Added Pleroma.Upload.Filter.Exiftool as an alternate EXIF stripping mechanism targeting GPS/location metadata.
+- "By approval" registrations mode.
 - Configuration: Added `:welcome` settings for the welcome message to newly registered users.
 
 <details>
diff --git a/config/config.exs b/config/config.exs
index 903a92cca..857e0afbb 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -205,6 +205,7 @@ config :pleroma, :instance,
   registrations_open: true,
   invites_enabled: false,
   account_activation_required: false,
+  account_approval_required: false,
   federating: true,
   federation_incoming_replies_max_depth: 100,
   federation_reachability_timeout_days: 7,
@@ -237,6 +238,7 @@ config :pleroma, :instance,
   max_remote_account_fields: 20,
   account_field_name_length: 512,
   account_field_value_length: 2048,
+  registration_reason_length: 500,
   external_user_synchronization: true,
   extended_nickname_format: true,
   cleanup_attachments: false,
diff --git a/config/description.exs b/config/description.exs
index 9dc87824b..11fbe0d78 100644
--- a/config/description.exs
+++ b/config/description.exs
@@ -661,6 +661,11 @@ config :pleroma, :config_description, [
         type: :boolean,
         description: "Require users to confirm their emails before signing in"
       },
+      %{
+        key: :account_approval_required,
+        type: :boolean,
+        description: "Require users to be manually approved by an admin before signing in"
+      },
       %{
         key: :federating,
         type: :boolean,
@@ -874,6 +879,14 @@ config :pleroma, :config_description, [
           2048
         ]
       },
+      %{
+        key: :registration_reason_length,
+        type: :integer,
+        description: "Maximum registration reason length. Default: 500.",
+        suggestions: [
+          500
+        ]
+      },
       %{
         key: :external_user_synchronization,
         type: :boolean,
diff --git a/docs/API/admin_api.md b/docs/API/admin_api.md
index baf895d90..4b143e4ee 100644
--- a/docs/API/admin_api.md
+++ b/docs/API/admin_api.md
@@ -19,6 +19,7 @@ Configuration options:
     - `local`: only local users
     - `external`: only external users
     - `active`: only active users
+    - `need_approval`: only unapproved users
     - `deactivated`: only deactivated users
     - `is_admin`: users with admin role
     - `is_moderator`: users with moderator role
@@ -46,7 +47,10 @@ Configuration options:
       "local": bool,
       "tags": array,
       "avatar": string,
-      "display_name": string
+      "display_name": string,
+      "confirmation_pending": bool,
+      "approval_pending": bool,
+      "registration_reason": string,
     },
     ...
   ]
@@ -242,6 +246,24 @@ Note: Available `:permission_group` is currently moderator and admin. 404 is ret
 }
 ```
 
+## `PATCH /api/pleroma/admin/users/approve`
+
+### Approve user
+
+- Params:
+  - `nicknames`: nicknames array
+- Response:
+
+```json
+{
+  users: [
+    {
+      // user object
+    }
+  ]
+}
+```
+
 ## `GET /api/pleroma/admin/users/:nickname_or_id`
 
 ### Retrive the details of a user
diff --git a/docs/administration/CLI_tasks/release_environments.md b/docs/administration/CLI_tasks/release_environments.md
new file mode 100644
index 000000000..36ab43864
--- /dev/null
+++ b/docs/administration/CLI_tasks/release_environments.md
@@ -0,0 +1,9 @@
+# Generate release environment file
+
+```sh tab="OTP"
+ ./bin/pleroma_ctl release_env gen
+```
+
+```sh tab="From Source"
+mix pleroma.release_env gen
+```
diff --git a/docs/configuration/cheatsheet.md b/docs/configuration/cheatsheet.md
index 2971ea324..9c768abef 100644
--- a/docs/configuration/cheatsheet.md
+++ b/docs/configuration/cheatsheet.md
@@ -33,6 +33,7 @@ To add configuration to your config file, you can copy it from the base config.
 * `registrations_open`: Enable registrations for anyone, invitations can be enabled when false.
 * `invites_enabled`: Enable user invitations for admins (depends on `registrations_open: false`).
 * `account_activation_required`: Require users to confirm their emails before signing in.
+* `account_approval_required`: Require users to be manually approved by an admin before signing in.
 * `federating`: Enable federation with other instances.
 * `federation_incoming_replies_max_depth`: Max. depth of reply-to activities fetching on incoming federation, to prevent out-of-memory situations while fetching very long threads. If set to `nil`, threads of any depth will be fetched. Lower this value if you experience out-of-memory crashes.
 * `federation_reachability_timeout_days`: Timeout (in days) of each external federation target being unreachable prior to pausing federating to it.
@@ -58,6 +59,7 @@ To add configuration to your config file, you can copy it from the base config.
 * `max_remote_account_fields`: The maximum number of custom fields in the remote user profile (default: `20`).
 * `account_field_name_length`: An account field name maximum length (default: `512`).
 * `account_field_value_length`: An account field value maximum length (default: `2048`).
+* `registration_reason_length`: Maximum registration reason length (default: `500`).
 * `external_user_synchronization`: Enabling following/followers counters synchronization for external users.
 * `cleanup_attachments`: Remove attachments along with statuses. Does not affect duplicate files and attachments without status. Enabling this will increase load to database when deleting statuses on larger instances.
 * `show_reactions`: Let favourites and emoji reactions be viewed through the API (default: `true`).
diff --git a/docs/installation/otp_en.md b/docs/installation/otp_en.md
index e4f822d1c..338dfa7d0 100644
--- a/docs/installation/otp_en.md
+++ b/docs/installation/otp_en.md
@@ -121,6 +121,9 @@ chown -R pleroma /etc/pleroma
 # Run the config generator
 su pleroma -s $SHELL -lc "./bin/pleroma_ctl instance gen --output /etc/pleroma/config.exs --output-psql /tmp/setup_db.psql"
 
+# Run the environment file generator.
+su pleroma -s $SHELL -lc "./bin/pleroma_ctl release_env gen"
+
 # Create the postgres database
 su postgres -s $SHELL -lc "psql -f /tmp/setup_db.psql"
 
@@ -131,7 +134,7 @@ su pleroma -s $SHELL -lc "./bin/pleroma_ctl migrate"
 # su pleroma -s $SHELL -lc "./bin/pleroma_ctl migrate --migrations-path priv/repo/optional_migrations/rum_indexing/"
 
 # Start the instance to verify that everything is working as expected
-su pleroma -s $SHELL -lc "./bin/pleroma daemon"
+su pleroma -s $SHELL -lc "export $(cat /opt/pleroma/config/pleroma.env); ./bin/pleroma daemon"
 
 # Wait for about 20 seconds and query the instance endpoint, if it shows your uri, name and email correctly, you are configured correctly
 sleep 20 && curl http://localhost:4000/api/v1/instance
@@ -200,6 +203,7 @@ rc-update add pleroma
 # Copy the service into a proper directory
 cp /opt/pleroma/installation/pleroma.service /etc/systemd/system/pleroma.service
 
+
 # Start pleroma and enable it on boot
 systemctl start pleroma
 systemctl enable pleroma
@@ -275,4 +279,3 @@ This will create an account withe the username of 'joeuser' with the email addre
 ## Questions
 
 Questions about the installation or didn’t it work as it should be, ask in [#pleroma:matrix.org](https://matrix.heldscal.la/#/room/#freenode_#pleroma:matrix.org) or IRC Channel **#pleroma** on **Freenode**.
-
diff --git a/installation/init.d/pleroma b/installation/init.d/pleroma
index 384536f7e..e908cda1b 100755
--- a/installation/init.d/pleroma
+++ b/installation/init.d/pleroma
@@ -8,6 +8,7 @@ pidfile="/var/run/pleroma.pid"
 directory=/opt/pleroma
 healthcheck_delay=60
 healthcheck_timer=30
+export $(cat /opt/pleroma/config/pleroma.env)
 
 : ${pleroma_port:-4000}
 
diff --git a/installation/pleroma.service b/installation/pleroma.service
index 5dcbc1387..ee00a3b7a 100644
--- a/installation/pleroma.service
+++ b/installation/pleroma.service
@@ -17,6 +17,8 @@ Environment="MIX_ENV=prod"
 Environment="HOME=/var/lib/pleroma"
 ; Path to the folder containing the Pleroma installation.
 WorkingDirectory=/opt/pleroma
+; Path to the environment file. the file contains RELEASE_COOKIE and etc 
+EnvironmentFile=/opt/pleroma/config/pleroma.env
 ; Path to the Mix binary.
 ExecStart=/usr/bin/mix phx.server
 
diff --git a/lib/mix/tasks/pleroma/release_env.ex b/lib/mix/tasks/pleroma/release_env.ex
new file mode 100644
index 000000000..9da74ffcf
--- /dev/null
+++ b/lib/mix/tasks/pleroma/release_env.ex
@@ -0,0 +1,76 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Mix.Tasks.Pleroma.ReleaseEnv do
+  use Mix.Task
+  import Mix.Pleroma
+
+  @shortdoc "Generate Pleroma environment file."
+  @moduledoc File.read!("docs/administration/CLI_tasks/release_environments.md")
+
+  def run(["gen" | rest]) do
+    {options, [], []} =
+      OptionParser.parse(
+        rest,
+        strict: [
+          force: :boolean,
+          path: :string
+        ],
+        aliases: [
+          p: :path,
+          f: :force
+        ]
+      )
+
+    file_path =
+      get_option(
+        options,
+        :path,
+        "Environment file path",
+        "./config/pleroma.env"
+      )
+
+    env_path = Path.expand(file_path)
+
+    proceed? =
+      if File.exists?(env_path) do
+        get_option(
+          options,
+          :force,
+          "Environment file already exists. Do you want to overwrite the #{env_path} file? (y/n)",
+          "n"
+        ) === "y"
+      else
+        true
+      end
+
+    if proceed? do
+      case do_generate(env_path) do
+        {:error, reason} ->
+          shell_error(
+            File.Error.message(%{action: "write to file", reason: reason, path: env_path})
+          )
+
+        _ ->
+          shell_info("\nThe file generated: #{env_path}.\n")
+
+          shell_info("""
+          WARNING: before start pleroma app please make sure to make the file read-only and non-modifiable.
+            Example:
+              chmod 0444 #{file_path}
+              chattr +i #{file_path}
+          """)
+      end
+    else
+      shell_info("\nThe file is exist. #{env_path}.\n")
+    end
+  end
+
+  def do_generate(path) do
+    content = "RELEASE_COOKIE=#{Base.encode32(:crypto.strong_rand_bytes(32))}"
+
+    File.mkdir_p!(Path.dirname(path))
+    File.write(path, content)
+  end
+end
diff --git a/lib/pleroma/emails/admin_email.ex b/lib/pleroma/emails/admin_email.ex
index aa0b2a66b..c27ad1065 100644
--- a/lib/pleroma/emails/admin_email.ex
+++ b/lib/pleroma/emails/admin_email.ex
@@ -8,6 +8,7 @@ defmodule Pleroma.Emails.AdminEmail do
   import Swoosh.Email
 
   alias Pleroma.Config
+  alias Pleroma.HTML
   alias Pleroma.Web.Router.Helpers
 
   defp instance_config, do: Config.get(:instance)
@@ -82,4 +83,18 @@ defmodule Pleroma.Emails.AdminEmail do
     |> subject("#{instance_name()} Report")
     |> html_body(html_body)
   end
+
+  def new_unapproved_registration(to, account) do
+    html_body = """
+    <p>New account for review: <a href="#{user_url(account)}">@#{account.nickname}</a></p>
+    <blockquote>#{HTML.strip_tags(account.registration_reason)}</blockquote>
+    <a href="#{Pleroma.Web.base_url()}/pleroma/admin">Visit AdminFE</a>
+    """
+
+    new()
+    |> to({to.name, to.email})
+    |> from({instance_name(), instance_notify_email()})
+    |> subject("New account up for review on #{instance_name()} (@#{account.nickname})")
+    |> html_body(html_body)
+  end
 end
diff --git a/lib/pleroma/gun/connection_pool.ex b/lib/pleroma/gun/connection_pool.ex
index c6894be53..49e9885bb 100644
--- a/lib/pleroma/gun/connection_pool.ex
+++ b/lib/pleroma/gun/connection_pool.ex
@@ -45,7 +45,7 @@ defmodule Pleroma.Gun.ConnectionPool do
     # so instead we use cast + monitor
 
     ref = Process.monitor(worker_pid)
-    if register, do: GenServer.cast(worker_pid, {:add_client, self(), true})
+    if register, do: GenServer.cast(worker_pid, {:add_client, self()})
 
     receive do
       {:conn_pid, pid} ->
diff --git a/lib/pleroma/gun/connection_pool/worker.ex b/lib/pleroma/gun/connection_pool/worker.ex
index a61892c60..fec9d0efa 100644
--- a/lib/pleroma/gun/connection_pool/worker.ex
+++ b/lib/pleroma/gun/connection_pool/worker.ex
@@ -36,10 +36,18 @@ defmodule Pleroma.Gun.ConnectionPool.Worker do
   end
 
   @impl true
-  def handle_cast({:add_client, client_pid, send}, state) do
+  def handle_cast({:add_client, client_pid}, state) do
     case handle_call(:add_client, {client_pid, nil}, state) do
       {:reply, conn_pid, state, :hibernate} ->
-        if send, do: send(client_pid, {:conn_pid, conn_pid})
+        send(client_pid, {:conn_pid, conn_pid})
+        {:noreply, state, :hibernate}
+    end
+  end
+
+  @impl true
+  def handle_cast({:remove_client, client_pid}, state) do
+    case handle_call(:remove_client, {client_pid, nil}, state) do
+      {:reply, _, state, :hibernate} ->
         {:noreply, state, :hibernate}
     end
   end
@@ -115,7 +123,7 @@ defmodule Pleroma.Gun.ConnectionPool.Worker do
       %{key: state.key}
     )
 
-    handle_cast({:remove_client, pid, false}, state)
+    handle_cast({:remove_client, pid}, state)
   end
 
   # LRFU policy: https://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.55.1478
diff --git a/lib/pleroma/moderation_log.ex b/lib/pleroma/moderation_log.ex
index 7aacd9d80..31c9afe2a 100644
--- a/lib/pleroma/moderation_log.ex
+++ b/lib/pleroma/moderation_log.ex
@@ -409,6 +409,17 @@ defmodule Pleroma.ModerationLog do
     "@#{actor_nickname} deactivated users: #{users_to_nicknames_string(users)}"
   end
 
+  @spec get_log_entry_message(ModerationLog) :: String.t()
+  def get_log_entry_message(%ModerationLog{
+        data: %{
+          "actor" => %{"nickname" => actor_nickname},
+          "action" => "approve",
+          "subject" => users
+        }
+      }) do
+    "@#{actor_nickname} approved users: #{users_to_nicknames_string(users)}"
+  end
+
   @spec get_log_entry_message(ModerationLog) :: String.t()
   def get_log_entry_message(%ModerationLog{
         data: %{
diff --git a/lib/pleroma/user.ex b/lib/pleroma/user.ex
index ed1db04c9..dcf6ebee2 100644
--- a/lib/pleroma/user.ex
+++ b/lib/pleroma/user.ex
@@ -42,7 +42,12 @@ defmodule Pleroma.User do
   require Logger
 
   @type t :: %__MODULE__{}
-  @type account_status :: :active | :deactivated | :password_reset_pending | :confirmation_pending
+  @type account_status ::
+          :active
+          | :deactivated
+          | :password_reset_pending
+          | :confirmation_pending
+          | :approval_pending
   @primary_key {:id, FlakeId.Ecto.CompatType, autogenerate: true}
 
   # credo:disable-for-next-line Credo.Check.Readability.MaxLineLength
@@ -106,6 +111,8 @@ defmodule Pleroma.User do
     field(:locked, :boolean, default: false)
     field(:confirmation_pending, :boolean, default: false)
     field(:password_reset_pending, :boolean, default: false)
+    field(:approval_pending, :boolean, default: false)
+    field(:registration_reason, :string, default: nil)
     field(:confirmation_token, :string, default: nil)
     field(:default_scope, :string, default: "public")
     field(:domain_blocks, {:array, :string}, default: [])
@@ -262,6 +269,7 @@ defmodule Pleroma.User do
   @spec account_status(User.t()) :: account_status()
   def account_status(%User{deactivated: true}), do: :deactivated
   def account_status(%User{password_reset_pending: true}), do: :password_reset_pending
+  def account_status(%User{approval_pending: true}), do: :approval_pending
 
   def account_status(%User{confirmation_pending: true}) do
     if Config.get([:instance, :account_activation_required]) do
@@ -633,6 +641,7 @@ defmodule Pleroma.User do
   def register_changeset(struct, params \\ %{}, opts \\ []) do
     bio_limit = Config.get([:instance, :user_bio_length], 5000)
     name_limit = Config.get([:instance, :user_name_length], 100)
+    reason_limit = Config.get([:instance, :registration_reason_length], 500)
     params = Map.put_new(params, :accepts_chat_messages, true)
 
     need_confirmation? =
@@ -642,8 +651,16 @@ defmodule Pleroma.User do
         opts[:need_confirmation]
       end
 
+    need_approval? =
+      if is_nil(opts[:need_approval]) do
+        Config.get([:instance, :account_approval_required])
+      else
+        opts[:need_approval]
+      end
+
     struct
     |> confirmation_changeset(need_confirmation: need_confirmation?)
+    |> approval_changeset(need_approval: need_approval?)
     |> cast(params, [
       :bio,
       :raw_bio,
@@ -653,7 +670,8 @@ defmodule Pleroma.User do
       :password,
       :password_confirmation,
       :emoji,
-      :accepts_chat_messages
+      :accepts_chat_messages,
+      :registration_reason
     ])
     |> validate_required([:name, :nickname, :password, :password_confirmation])
     |> validate_confirmation(:password)
@@ -664,6 +682,7 @@ defmodule Pleroma.User do
     |> validate_format(:email, @email_regex)
     |> validate_length(:bio, max: bio_limit)
     |> validate_length(:name, min: 1, max: name_limit)
+    |> validate_length(:registration_reason, max: reason_limit)
     |> maybe_validate_required_email(opts[:external])
     |> put_password_hash
     |> put_ap_id()
@@ -1494,6 +1513,19 @@ defmodule Pleroma.User do
     end
   end
 
+  def approve(users) when is_list(users) do
+    Repo.transaction(fn ->
+      Enum.map(users, fn user ->
+        with {:ok, user} <- approve(user), do: user
+      end)
+    end)
+  end
+
+  def approve(%User{} = user) do
+    change(user, approval_pending: false)
+    |> update_and_set_cache()
+  end
+
   def update_notification_settings(%User{} = user, settings) do
     user
     |> cast(%{notification_settings: settings}, [])
@@ -1520,12 +1552,17 @@ defmodule Pleroma.User do
   defp delete_or_deactivate(%User{local: true} = user) do
     status = account_status(user)
 
-    if status == :confirmation_pending do
-      delete_and_invalidate_cache(user)
-    else
-      user
-      |> change(%{deactivated: true, email: nil})
-      |> update_and_set_cache()
+    case status do
+      :confirmation_pending ->
+        delete_and_invalidate_cache(user)
+
+      :approval_pending ->
+        delete_and_invalidate_cache(user)
+
+      _ ->
+        user
+        |> change(%{deactivated: true, email: nil})
+        |> update_and_set_cache()
     end
   end
 
@@ -2178,6 +2215,12 @@ defmodule Pleroma.User do
     cast(user, params, [:confirmation_pending, :confirmation_token])
   end
 
+  @spec approval_changeset(User.t(), keyword()) :: Changeset.t()
+  def approval_changeset(user, need_approval: need_approval?) do
+    params = if need_approval?, do: %{approval_pending: true}, else: %{approval_pending: false}
+    cast(user, params, [:approval_pending])
+  end
+
   def add_pinnned_activity(user, %Pleroma.Activity{id: id}) do
     if id not in user.pinned_activities do
       max_pinned_statuses = Config.get([:instance, :max_pinned_statuses], 0)
diff --git a/lib/pleroma/user/query.ex b/lib/pleroma/user/query.ex
index 66ffe9090..45553cb6c 100644
--- a/lib/pleroma/user/query.ex
+++ b/lib/pleroma/user/query.ex
@@ -42,6 +42,7 @@ defmodule Pleroma.User.Query do
             external: boolean(),
             active: boolean(),
             deactivated: boolean(),
+            need_approval: boolean(),
             is_admin: boolean(),
             is_moderator: boolean(),
             super_users: boolean(),
@@ -146,6 +147,10 @@ defmodule Pleroma.User.Query do
     |> where([u], not is_nil(u.nickname))
   end
 
+  defp compose_query({:need_approval, _}, query) do
+    where(query, [u], u.approval_pending)
+  end
+
   defp compose_query({:followers, %User{id: id}}, query) do
     query
     |> where([u], u.id != ^id)
diff --git a/lib/pleroma/web/activity_pub/mrf/ensure_re_prepended.ex b/lib/pleroma/web/activity_pub/mrf/ensure_re_prepended.ex
index 2627a0007..3bf70b894 100644
--- a/lib/pleroma/web/activity_pub/mrf/ensure_re_prepended.ex
+++ b/lib/pleroma/web/activity_pub/mrf/ensure_re_prepended.ex
@@ -27,7 +27,8 @@ defmodule Pleroma.Web.ActivityPub.MRF.EnsureRePrepended do
 
   def filter_by_summary(_in_reply_to, child), do: child
 
-  def filter(%{"type" => "Create", "object" => child_object} = object) do
+  def filter(%{"type" => "Create", "object" => child_object} = object)
+      when is_map(child_object) do
     child =
       child_object["inReplyTo"]
       |> Object.normalize(child_object["inReplyTo"])
diff --git a/lib/pleroma/web/admin_api/controllers/admin_api_controller.ex b/lib/pleroma/web/admin_api/controllers/admin_api_controller.ex
index 5101e28d6..aa2af1ab5 100644
--- a/lib/pleroma/web/admin_api/controllers/admin_api_controller.ex
+++ b/lib/pleroma/web/admin_api/controllers/admin_api_controller.ex
@@ -44,6 +44,7 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIController do
            :user_toggle_activation,
            :user_activate,
            :user_deactivate,
+           :user_approve,
            :tag_users,
            :untag_users,
            :right_add,
@@ -303,6 +304,21 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIController do
     |> render("index.json", %{users: Keyword.values(updated_users)})
   end
 
+  def user_approve(%{assigns: %{user: admin}} = conn, %{"nicknames" => nicknames}) do
+    users = Enum.map(nicknames, &User.get_cached_by_nickname/1)
+    {:ok, updated_users} = User.approve(users)
+
+    ModerationLog.insert_log(%{
+      actor: admin,
+      subject: users,
+      action: "approve"
+    })
+
+    conn
+    |> put_view(AccountView)
+    |> render("index.json", %{users: updated_users})
+  end
+
   def tag_users(%{assigns: %{user: admin}} = conn, %{"nicknames" => nicknames, "tags" => tags}) do
     with {:ok, _} <- User.tag(nicknames, tags) do
       ModerationLog.insert_log(%{
@@ -354,7 +370,7 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIController do
     end
   end
 
-  @filters ~w(local external active deactivated is_admin is_moderator)
+  @filters ~w(local external active deactivated need_approval is_admin is_moderator)
 
   @spec maybe_parse_filters(String.t()) :: %{required(String.t()) => true} | %{}
   defp maybe_parse_filters(filters) when is_nil(filters) or filters == "", do: %{}
diff --git a/lib/pleroma/web/admin_api/views/account_view.ex b/lib/pleroma/web/admin_api/views/account_view.ex
index 88fbb5315..333e72e42 100644
--- a/lib/pleroma/web/admin_api/views/account_view.ex
+++ b/lib/pleroma/web/admin_api/views/account_view.ex
@@ -77,7 +77,9 @@ defmodule Pleroma.Web.AdminAPI.AccountView do
       "roles" => User.roles(user),
       "tags" => user.tags || [],
       "confirmation_pending" => user.confirmation_pending,
-      "url" => user.uri || user.ap_id
+      "approval_pending" => user.approval_pending,
+      "url" => user.uri || user.ap_id,
+      "registration_reason" => user.registration_reason
     }
   end
 
diff --git a/lib/pleroma/web/feed/user_controller.ex b/lib/pleroma/web/feed/user_controller.ex
index d56f43818..9cd334a33 100644
--- a/lib/pleroma/web/feed/user_controller.ex
+++ b/lib/pleroma/web/feed/user_controller.ex
@@ -47,7 +47,7 @@ defmodule Pleroma.Web.Feed.UserController do
         "atom"
       end
 
-    with {_, %User{} = user} <- {:fetch_user, User.get_cached_by_nickname(nickname)} do
+    with {_, %User{local: true} = user} <- {:fetch_user, User.get_cached_by_nickname(nickname)} do
       activities =
         %{
           type: ["Create"],
@@ -71,6 +71,7 @@ defmodule Pleroma.Web.Feed.UserController do
     render_error(conn, :not_found, "Not found")
   end
 
+  def errors(conn, {:fetch_user, %User{local: false}}), do: errors(conn, {:error, :not_found})
   def errors(conn, {:fetch_user, nil}), do: errors(conn, {:error, :not_found})
 
   def errors(conn, _) do
diff --git a/lib/pleroma/web/mastodon_api/views/instance_view.ex b/lib/pleroma/web/mastodon_api/views/instance_view.ex
index cd3bc7f00..ea2d3aa9c 100644
--- a/lib/pleroma/web/mastodon_api/views/instance_view.ex
+++ b/lib/pleroma/web/mastodon_api/views/instance_view.ex
@@ -26,6 +26,7 @@ defmodule Pleroma.Web.MastodonAPI.InstanceView do
       thumbnail: Keyword.get(instance, :instance_thumbnail),
       languages: ["en"],
       registrations: Keyword.get(instance, :registrations_open),
+      approval_required: Keyword.get(instance, :account_approval_required),
       # Extra (not present in Mastodon):
       max_toot_chars: Keyword.get(instance, :limit),
       poll_limits: Keyword.get(instance, :poll_limits),
diff --git a/lib/pleroma/web/oauth/oauth_controller.ex b/lib/pleroma/web/oauth/oauth_controller.ex
index 7683589cf..61fe81d33 100644
--- a/lib/pleroma/web/oauth/oauth_controller.ex
+++ b/lib/pleroma/web/oauth/oauth_controller.ex
@@ -337,6 +337,16 @@ defmodule Pleroma.Web.OAuth.OAuthController do
     )
   end
 
+  defp handle_token_exchange_error(%Plug.Conn{} = conn, {:account_status, :approval_pending}) do
+    render_error(
+      conn,
+      :forbidden,
+      "Your account is awaiting approval.",
+      %{},
+      "awaiting_approval"
+    )
+  end
+
   defp handle_token_exchange_error(%Plug.Conn{} = conn, _error) do
     render_invalid_credentials_error(conn)
   end
diff --git a/lib/pleroma/web/router.ex b/lib/pleroma/web/router.ex
index 386308362..c6433cc53 100644
--- a/lib/pleroma/web/router.ex
+++ b/lib/pleroma/web/router.ex
@@ -138,6 +138,7 @@ defmodule Pleroma.Web.Router do
     patch("/users/:nickname/toggle_activation", AdminAPIController, :user_toggle_activation)
     patch("/users/activate", AdminAPIController, :user_activate)
     patch("/users/deactivate", AdminAPIController, :user_deactivate)
+    patch("/users/approve", AdminAPIController, :user_approve)
     put("/users/tag", AdminAPIController, :tag_users)
     delete("/users/tag", AdminAPIController, :untag_users)
 
diff --git a/lib/pleroma/web/twitter_api/twitter_api.ex b/lib/pleroma/web/twitter_api/twitter_api.ex
index 5cfb385ac..2294d9d0d 100644
--- a/lib/pleroma/web/twitter_api/twitter_api.ex
+++ b/lib/pleroma/web/twitter_api/twitter_api.ex
@@ -19,6 +19,7 @@ defmodule Pleroma.Web.TwitterAPI.TwitterAPI do
       |> Map.put(:nickname, params[:username])
       |> Map.put(:name, Map.get(params, :fullname, params[:username]))
       |> Map.put(:password_confirmation, params[:password])
+      |> Map.put(:registration_reason, params[:reason])
 
     if Pleroma.Config.get([:instance, :registrations_open]) do
       create_user(params, opts)
@@ -44,6 +45,7 @@ defmodule Pleroma.Web.TwitterAPI.TwitterAPI do
 
     case User.register(changeset) do
       {:ok, user} ->
+        maybe_notify_admins(user)
         {:ok, user}
 
       {:error, changeset} ->
@@ -56,6 +58,18 @@ defmodule Pleroma.Web.TwitterAPI.TwitterAPI do
     end
   end
 
+  defp maybe_notify_admins(%User{} = account) do
+    if Pleroma.Config.get([:instance, :account_approval_required]) do
+      User.all_superusers()
+      |> Enum.filter(fn user -> not is_nil(user.email) end)
+      |> Enum.each(fn superuser ->
+        superuser
+        |> Pleroma.Emails.AdminEmail.new_unapproved_registration(account)
+        |> Pleroma.Emails.Mailer.deliver_async()
+      end)
+    end
+  end
+
   def password_reset(nickname_or_email) do
     with true <- is_binary(nickname_or_email),
          %User{local: true, email: email} = user when is_binary(email) <-
diff --git a/priv/repo/migrations/20200712234852_add_approval_fields_to_users.exs b/priv/repo/migrations/20200712234852_add_approval_fields_to_users.exs
new file mode 100644
index 000000000..43f741a5b
--- /dev/null
+++ b/priv/repo/migrations/20200712234852_add_approval_fields_to_users.exs
@@ -0,0 +1,10 @@
+defmodule Pleroma.Repo.Migrations.AddApprovalFieldsToUsers do
+  use Ecto.Migration
+
+  def change do
+    alter table(:users) do
+      add(:approval_pending, :boolean)
+      add(:registration_reason, :text)
+    end
+  end
+end
diff --git a/test/emails/admin_email_test.exs b/test/emails/admin_email_test.exs
index 9082ae5a7..e24231e27 100644
--- a/test/emails/admin_email_test.exs
+++ b/test/emails/admin_email_test.exs
@@ -46,4 +46,24 @@ defmodule Pleroma.Emails.AdminEmailTest do
     assert res.to == [{to_user.name, to_user.email}]
     assert res.from == {config[:name], config[:notify_email]}
   end
+
+  test "new unapproved registration email" do
+    config = Pleroma.Config.get(:instance)
+    to_user = insert(:user)
+    account = insert(:user, registration_reason: "Plz let me in")
+
+    res = AdminEmail.new_unapproved_registration(to_user, account)
+
+    account_url = Helpers.user_feed_url(Pleroma.Web.Endpoint, :feed_redirect, account.id)
+
+    assert res.to == [{to_user.name, to_user.email}]
+    assert res.from == {config[:name], config[:notify_email]}
+    assert res.subject == "New account up for review on #{config[:name]} (@#{account.nickname})"
+
+    assert res.html_body == """
+           <p>New account for review: <a href="#{account_url}">@#{account.nickname}</a></p>
+           <blockquote>Plz let me in</blockquote>
+           <a href="http://localhost:4001/pleroma/admin">Visit AdminFE</a>
+           """
+  end
 end
diff --git a/test/tasks/release_env_test.exs b/test/tasks/release_env_test.exs
new file mode 100644
index 000000000..519f1eba9
--- /dev/null
+++ b/test/tasks/release_env_test.exs
@@ -0,0 +1,30 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2020 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Mix.Tasks.Pleroma.ReleaseEnvTest do
+  use ExUnit.Case
+  import ExUnit.CaptureIO, only: [capture_io: 1]
+
+  @path "config/pleroma.test.env"
+
+  def do_clean do
+    if File.exists?(@path) do
+      File.rm_rf(@path)
+    end
+  end
+
+  setup do
+    do_clean()
+    on_exit(fn -> do_clean() end)
+    :ok
+  end
+
+  test "generate pleroma.env" do
+    assert capture_io(fn ->
+             Mix.Tasks.Pleroma.ReleaseEnv.run(["gen", "--path", @path, "--force"])
+           end) =~ "The file generated"
+
+    assert File.read!(@path) =~ "RELEASE_COOKIE="
+  end
+end
diff --git a/test/user_test.exs b/test/user_test.exs
index d087e9101..624baf8ad 100644
--- a/test/user_test.exs
+++ b/test/user_test.exs
@@ -543,6 +543,46 @@ defmodule Pleroma.UserTest do
     end
   end
 
+  describe "user registration, with :account_approval_required" do
+    @full_user_data %{
+      bio: "A guy",
+      name: "my name",
+      nickname: "nick",
+      password: "test",
+      password_confirmation: "test",
+      email: "email@example.com",
+      registration_reason: "I'm a cool guy :)"
+    }
+    setup do: clear_config([:instance, :account_approval_required], true)
+
+    test "it creates unapproved user" do
+      changeset = User.register_changeset(%User{}, @full_user_data)
+      assert changeset.valid?
+
+      {:ok, user} = Repo.insert(changeset)
+
+      assert user.approval_pending
+      assert user.registration_reason == "I'm a cool guy :)"
+    end
+
+    test "it restricts length of registration reason" do
+      reason_limit = Pleroma.Config.get([:instance, :registration_reason_length])
+
+      assert is_integer(reason_limit)
+
+      params =
+        @full_user_data
+        |> Map.put(
+          :registration_reason,
+          "Quia et nesciunt dolores numquam ipsam nisi sapiente soluta. Ullam repudiandae nisi quam porro officiis officiis ad. Consequatur animi velit ex quia. Odit voluptatem perferendis quia ut nisi. Dignissimos sit soluta atque aliquid dolorem ut dolorum ut. Labore voluptates iste iusto amet voluptatum earum. Ad fugit illum nam eos ut nemo. Pariatur ea fuga non aspernatur. Dignissimos debitis officia corporis est nisi ab et. Atque itaque alias eius voluptas minus. Accusamus numquam tempore occaecati in."
+        )
+
+      changeset = User.register_changeset(%User{}, params)
+
+      refute changeset.valid?
+    end
+  end
+
   describe "get_or_fetch/1" do
     test "gets an existing user by nickname" do
       user = insert(:user)
@@ -1208,6 +1248,31 @@ defmodule Pleroma.UserTest do
     end
   end
 
+  describe "approve" do
+    test "approves a user" do
+      user = insert(:user, approval_pending: true)
+      assert true == user.approval_pending
+      {:ok, user} = User.approve(user)
+      assert false == user.approval_pending
+    end
+
+    test "approves a list of users" do
+      unapproved_users = [
+        insert(:user, approval_pending: true),
+        insert(:user, approval_pending: true),
+        insert(:user, approval_pending: true)
+      ]
+
+      {:ok, users} = User.approve(unapproved_users)
+
+      assert Enum.count(users) == 3
+
+      Enum.each(users, fn user ->
+        assert false == user.approval_pending
+      end)
+    end
+  end
+
   describe "delete" do
     setup do
       {:ok, user} = insert(:user) |> User.set_cache()
@@ -1295,6 +1360,17 @@ defmodule Pleroma.UserTest do
     end
   end
 
+  test "delete/1 when approval is pending deletes the user" do
+    user = insert(:user, approval_pending: true)
+    {:ok, user: user}
+
+    {:ok, job} = User.delete(user)
+    {:ok, _} = ObanHelpers.perform(job)
+
+    refute User.get_cached_by_id(user.id)
+    refute User.get_by_id(user.id)
+  end
+
   test "get_public_key_for_ap_id fetches a user that's not in the db" do
     assert {:ok, _key} = User.get_public_key_for_ap_id("http://mastodon.example.org/users/admin")
   end
@@ -1369,6 +1445,14 @@ defmodule Pleroma.UserTest do
       user = insert(:user, local: true, confirmation_pending: false, deactivated: true)
       assert User.account_status(user) == :deactivated
     end
+
+    test "returns :approval_pending for unapproved user" do
+      user = insert(:user, local: true, approval_pending: true)
+      assert User.account_status(user) == :approval_pending
+
+      user = insert(:user, local: true, confirmation_pending: true, approval_pending: true)
+      assert User.account_status(user) == :approval_pending
+    end
   end
 
   describe "superuser?/1" do
diff --git a/test/web/activity_pub/mrf/ensure_re_prepended_test.exs b/test/web/activity_pub/mrf/ensure_re_prepended_test.exs
index 38ddec5bb..9a283f27d 100644
--- a/test/web/activity_pub/mrf/ensure_re_prepended_test.exs
+++ b/test/web/activity_pub/mrf/ensure_re_prepended_test.exs
@@ -78,5 +78,15 @@ defmodule Pleroma.Web.ActivityPub.MRF.EnsureRePrependedTest do
       assert {:ok, res} = EnsureRePrepended.filter(message)
       assert res == message
     end
+
+    test "it skips if the object is only a reference" do
+      message = %{
+        "type" => "Create",
+        "object" => "somereference"
+      }
+
+      assert {:ok, res} = EnsureRePrepended.filter(message)
+      assert res == message
+    end
   end
 end
diff --git a/test/web/admin_api/controllers/admin_api_controller_test.exs b/test/web/admin_api/controllers/admin_api_controller_test.exs
index 6082441ee..b5d5bd8c7 100644
--- a/test/web/admin_api/controllers/admin_api_controller_test.exs
+++ b/test/web/admin_api/controllers/admin_api_controller_test.exs
@@ -349,7 +349,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
         "avatar" => User.avatar_url(user) |> MediaProxy.url(),
         "display_name" => HTML.strip_tags(user.name || user.nickname),
         "confirmation_pending" => false,
-        "url" => user.ap_id
+        "approval_pending" => false,
+        "url" => user.ap_id,
+        "registration_reason" => nil
       }
 
       assert expected == json_response(conn, 200)
@@ -613,6 +615,8 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
   describe "GET /api/pleroma/admin/users" do
     test "renders users array for the first page", %{conn: conn, admin: admin} do
       user = insert(:user, local: false, tags: ["foo", "bar"])
+      user2 = insert(:user, approval_pending: true, registration_reason: "I'm a chill dude")
+
       conn = get(conn, "/api/pleroma/admin/users?page=1")
 
       users =
@@ -627,7 +631,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
             "avatar" => User.avatar_url(admin) |> MediaProxy.url(),
             "display_name" => HTML.strip_tags(admin.name || admin.nickname),
             "confirmation_pending" => false,
-            "url" => admin.ap_id
+            "approval_pending" => false,
+            "url" => admin.ap_id,
+            "registration_reason" => nil
           },
           %{
             "deactivated" => user.deactivated,
@@ -639,13 +645,29 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
             "avatar" => User.avatar_url(user) |> MediaProxy.url(),
             "display_name" => HTML.strip_tags(user.name || user.nickname),
             "confirmation_pending" => false,
-            "url" => user.ap_id
+            "approval_pending" => false,
+            "url" => user.ap_id,
+            "registration_reason" => nil
+          },
+          %{
+            "deactivated" => user2.deactivated,
+            "id" => user2.id,
+            "nickname" => user2.nickname,
+            "roles" => %{"admin" => false, "moderator" => false},
+            "local" => true,
+            "tags" => [],
+            "avatar" => User.avatar_url(user2) |> MediaProxy.url(),
+            "display_name" => HTML.strip_tags(user2.name || user2.nickname),
+            "confirmation_pending" => false,
+            "approval_pending" => true,
+            "url" => user2.ap_id,
+            "registration_reason" => "I'm a chill dude"
           }
         ]
         |> Enum.sort_by(& &1["nickname"])
 
       assert json_response(conn, 200) == %{
-               "count" => 2,
+               "count" => 3,
                "page_size" => 50,
                "users" => users
              }
@@ -712,7 +734,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
                    "avatar" => User.avatar_url(user) |> MediaProxy.url(),
                    "display_name" => HTML.strip_tags(user.name || user.nickname),
                    "confirmation_pending" => false,
-                   "url" => user.ap_id
+                   "approval_pending" => false,
+                   "url" => user.ap_id,
+                   "registration_reason" => nil
                  }
                ]
              }
@@ -738,7 +762,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
                    "avatar" => User.avatar_url(user) |> MediaProxy.url(),
                    "display_name" => HTML.strip_tags(user.name || user.nickname),
                    "confirmation_pending" => false,
-                   "url" => user.ap_id
+                   "approval_pending" => false,
+                   "url" => user.ap_id,
+                   "registration_reason" => nil
                  }
                ]
              }
@@ -764,7 +790,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
                    "avatar" => User.avatar_url(user) |> MediaProxy.url(),
                    "display_name" => HTML.strip_tags(user.name || user.nickname),
                    "confirmation_pending" => false,
-                   "url" => user.ap_id
+                   "approval_pending" => false,
+                   "url" => user.ap_id,
+                   "registration_reason" => nil
                  }
                ]
              }
@@ -790,7 +818,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
                    "avatar" => User.avatar_url(user) |> MediaProxy.url(),
                    "display_name" => HTML.strip_tags(user.name || user.nickname),
                    "confirmation_pending" => false,
-                   "url" => user.ap_id
+                   "approval_pending" => false,
+                   "url" => user.ap_id,
+                   "registration_reason" => nil
                  }
                ]
              }
@@ -816,7 +846,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
                    "avatar" => User.avatar_url(user) |> MediaProxy.url(),
                    "display_name" => HTML.strip_tags(user.name || user.nickname),
                    "confirmation_pending" => false,
-                   "url" => user.ap_id
+                   "approval_pending" => false,
+                   "url" => user.ap_id,
+                   "registration_reason" => nil
                  }
                ]
              }
@@ -842,7 +874,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
                    "avatar" => User.avatar_url(user) |> MediaProxy.url(),
                    "display_name" => HTML.strip_tags(user.name || user.nickname),
                    "confirmation_pending" => false,
-                   "url" => user.ap_id
+                   "approval_pending" => false,
+                   "url" => user.ap_id,
+                   "registration_reason" => nil
                  }
                ]
              }
@@ -863,7 +897,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
                    "avatar" => User.avatar_url(user2) |> MediaProxy.url(),
                    "display_name" => HTML.strip_tags(user2.name || user2.nickname),
                    "confirmation_pending" => false,
-                   "url" => user2.ap_id
+                   "approval_pending" => false,
+                   "url" => user2.ap_id,
+                   "registration_reason" => nil
                  }
                ]
              }
@@ -896,7 +932,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
                    "avatar" => User.avatar_url(user) |> MediaProxy.url(),
                    "display_name" => HTML.strip_tags(user.name || user.nickname),
                    "confirmation_pending" => false,
-                   "url" => user.ap_id
+                   "approval_pending" => false,
+                   "url" => user.ap_id,
+                   "registration_reason" => nil
                  }
                ]
              }
@@ -922,7 +960,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
             "avatar" => User.avatar_url(user) |> MediaProxy.url(),
             "display_name" => HTML.strip_tags(user.name || user.nickname),
             "confirmation_pending" => false,
-            "url" => user.ap_id
+            "approval_pending" => false,
+            "url" => user.ap_id,
+            "registration_reason" => nil
           },
           %{
             "deactivated" => admin.deactivated,
@@ -934,7 +974,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
             "avatar" => User.avatar_url(admin) |> MediaProxy.url(),
             "display_name" => HTML.strip_tags(admin.name || admin.nickname),
             "confirmation_pending" => false,
-            "url" => admin.ap_id
+            "approval_pending" => false,
+            "url" => admin.ap_id,
+            "registration_reason" => nil
           },
           %{
             "deactivated" => false,
@@ -946,7 +988,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
             "avatar" => User.avatar_url(old_admin) |> MediaProxy.url(),
             "display_name" => HTML.strip_tags(old_admin.name || old_admin.nickname),
             "confirmation_pending" => false,
-            "url" => old_admin.ap_id
+            "approval_pending" => false,
+            "url" => old_admin.ap_id,
+            "registration_reason" => nil
           }
         ]
         |> Enum.sort_by(& &1["nickname"])
@@ -958,6 +1002,44 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
              }
     end
 
+    test "only unapproved users", %{conn: conn} do
+      user =
+        insert(:user,
+          nickname: "sadboy",
+          approval_pending: true,
+          registration_reason: "Plz let me in!"
+        )
+
+      insert(:user, nickname: "happyboy", approval_pending: false)
+
+      conn = get(conn, "/api/pleroma/admin/users?filters=need_approval")
+
+      users =
+        [
+          %{
+            "deactivated" => user.deactivated,
+            "id" => user.id,
+            "nickname" => user.nickname,
+            "roles" => %{"admin" => false, "moderator" => false},
+            "local" => true,
+            "tags" => [],
+            "avatar" => User.avatar_url(user) |> MediaProxy.url(),
+            "display_name" => HTML.strip_tags(user.name || user.nickname),
+            "confirmation_pending" => false,
+            "approval_pending" => true,
+            "url" => user.ap_id,
+            "registration_reason" => "Plz let me in!"
+          }
+        ]
+        |> Enum.sort_by(& &1["nickname"])
+
+      assert json_response(conn, 200) == %{
+               "count" => 1,
+               "page_size" => 50,
+               "users" => users
+             }
+    end
+
     test "load only admins", %{conn: conn, admin: admin} do
       second_admin = insert(:user, is_admin: true)
       insert(:user)
@@ -977,7 +1059,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
             "avatar" => User.avatar_url(admin) |> MediaProxy.url(),
             "display_name" => HTML.strip_tags(admin.name || admin.nickname),
             "confirmation_pending" => false,
-            "url" => admin.ap_id
+            "approval_pending" => false,
+            "url" => admin.ap_id,
+            "registration_reason" => nil
           },
           %{
             "deactivated" => false,
@@ -989,7 +1073,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
             "avatar" => User.avatar_url(second_admin) |> MediaProxy.url(),
             "display_name" => HTML.strip_tags(second_admin.name || second_admin.nickname),
             "confirmation_pending" => false,
-            "url" => second_admin.ap_id
+            "approval_pending" => false,
+            "url" => second_admin.ap_id,
+            "registration_reason" => nil
           }
         ]
         |> Enum.sort_by(& &1["nickname"])
@@ -1022,7 +1108,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
                    "avatar" => User.avatar_url(moderator) |> MediaProxy.url(),
                    "display_name" => HTML.strip_tags(moderator.name || moderator.nickname),
                    "confirmation_pending" => false,
-                   "url" => moderator.ap_id
+                   "approval_pending" => false,
+                   "url" => moderator.ap_id,
+                   "registration_reason" => nil
                  }
                ]
              }
@@ -1048,7 +1136,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
             "avatar" => User.avatar_url(user1) |> MediaProxy.url(),
             "display_name" => HTML.strip_tags(user1.name || user1.nickname),
             "confirmation_pending" => false,
-            "url" => user1.ap_id
+            "approval_pending" => false,
+            "url" => user1.ap_id,
+            "registration_reason" => nil
           },
           %{
             "deactivated" => false,
@@ -1060,7 +1150,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
             "avatar" => User.avatar_url(user2) |> MediaProxy.url(),
             "display_name" => HTML.strip_tags(user2.name || user2.nickname),
             "confirmation_pending" => false,
-            "url" => user2.ap_id
+            "approval_pending" => false,
+            "url" => user2.ap_id,
+            "registration_reason" => nil
           }
         ]
         |> Enum.sort_by(& &1["nickname"])
@@ -1100,7 +1192,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
                    "avatar" => User.avatar_url(user) |> MediaProxy.url(),
                    "display_name" => HTML.strip_tags(user.name || user.nickname),
                    "confirmation_pending" => false,
-                   "url" => user.ap_id
+                   "approval_pending" => false,
+                   "url" => user.ap_id,
+                   "registration_reason" => nil
                  }
                ]
              }
@@ -1125,7 +1219,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
                    "avatar" => User.avatar_url(admin) |> MediaProxy.url(),
                    "display_name" => HTML.strip_tags(admin.name || admin.nickname),
                    "confirmation_pending" => false,
-                   "url" => admin.ap_id
+                   "approval_pending" => false,
+                   "url" => admin.ap_id,
+                   "registration_reason" => nil
                  }
                ]
              }
@@ -1172,6 +1268,26 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
              "@#{admin.nickname} deactivated users: @#{user_one.nickname}, @#{user_two.nickname}"
   end
 
+  test "PATCH /api/pleroma/admin/users/approve", %{admin: admin, conn: conn} do
+    user_one = insert(:user, approval_pending: true)
+    user_two = insert(:user, approval_pending: true)
+
+    conn =
+      patch(
+        conn,
+        "/api/pleroma/admin/users/approve",
+        %{nicknames: [user_one.nickname, user_two.nickname]}
+      )
+
+    response = json_response(conn, 200)
+    assert Enum.map(response["users"], & &1["approval_pending"]) == [false, false]
+
+    log_entry = Repo.one(ModerationLog)
+
+    assert ModerationLog.get_log_entry_message(log_entry) ==
+             "@#{admin.nickname} approved users: @#{user_one.nickname}, @#{user_two.nickname}"
+  end
+
   test "PATCH /api/pleroma/admin/users/:nickname/toggle_activation", %{admin: admin, conn: conn} do
     user = insert(:user)
 
@@ -1188,7 +1304,9 @@ defmodule Pleroma.Web.AdminAPI.AdminAPIControllerTest do
                "avatar" => User.avatar_url(user) |> MediaProxy.url(),
                "display_name" => HTML.strip_tags(user.name || user.nickname),
                "confirmation_pending" => false,
-               "url" => user.ap_id
+               "approval_pending" => false,
+               "url" => user.ap_id,
+               "registration_reason" => nil
              }
 
     log_entry = Repo.one(ModerationLog)
diff --git a/test/web/admin_api/search_test.exs b/test/web/admin_api/search_test.exs
index e0e3d4153..b974cedd5 100644
--- a/test/web/admin_api/search_test.exs
+++ b/test/web/admin_api/search_test.exs
@@ -166,5 +166,16 @@ defmodule Pleroma.Web.AdminAPI.SearchTest do
       assert total == 3
       assert count == 1
     end
+
+    test "it returns unapproved user" do
+      unapproved = insert(:user, approval_pending: true)
+      insert(:user)
+      insert(:user)
+
+      {:ok, _results, total} = Search.user()
+      {:ok, [^unapproved], count} = Search.user(%{need_approval: true})
+      assert total == 3
+      assert count == 1
+    end
   end
 end
diff --git a/test/web/feed/user_controller_test.exs b/test/web/feed/user_controller_test.exs
index fa2ed1ea5..0d2a61967 100644
--- a/test/web/feed/user_controller_test.exs
+++ b/test/web/feed/user_controller_test.exs
@@ -181,6 +181,17 @@ defmodule Pleroma.Web.Feed.UserControllerTest do
 
       assert activity_titles == ['public', 'unlisted']
     end
+
+    test "returns 404 when the user is remote", %{conn: conn} do
+      user = insert(:user, local: false)
+
+      {:ok, _} = CommonAPI.post(user, %{status: "test"})
+
+      assert conn
+             |> put_req_header("accept", "application/atom+xml")
+             |> get(user_feed_path(conn, :feed, user.nickname))
+             |> response(404)
+    end
   end
 
   # Note: see ActivityPubControllerTest for JSON format tests
diff --git a/test/web/mastodon_api/controllers/account_controller_test.exs b/test/web/mastodon_api/controllers/account_controller_test.exs
index c304487ea..e6b283aab 100644
--- a/test/web/mastodon_api/controllers/account_controller_test.exs
+++ b/test/web/mastodon_api/controllers/account_controller_test.exs
@@ -904,6 +904,7 @@ defmodule Pleroma.Web.MastodonAPI.AccountControllerTest do
     end
 
     setup do: clear_config([:instance, :account_activation_required])
+    setup do: clear_config([:instance, :account_approval_required])
 
     test "Account registration via Application", %{conn: conn} do
       conn =
@@ -968,6 +969,75 @@ defmodule Pleroma.Web.MastodonAPI.AccountControllerTest do
       assert token_from_db.user.confirmation_pending
     end
 
+    test "Account registration via app with account_approval_required", %{conn: conn} do
+      Pleroma.Config.put([:instance, :account_approval_required], true)
+
+      conn =
+        conn
+        |> put_req_header("content-type", "application/json")
+        |> post("/api/v1/apps", %{
+          client_name: "client_name",
+          redirect_uris: "urn:ietf:wg:oauth:2.0:oob",
+          scopes: "read, write, follow"
+        })
+
+      assert %{
+               "client_id" => client_id,
+               "client_secret" => client_secret,
+               "id" => _,
+               "name" => "client_name",
+               "redirect_uri" => "urn:ietf:wg:oauth:2.0:oob",
+               "vapid_key" => _,
+               "website" => nil
+             } = json_response_and_validate_schema(conn, 200)
+
+      conn =
+        post(conn, "/oauth/token", %{
+          grant_type: "client_credentials",
+          client_id: client_id,
+          client_secret: client_secret
+        })
+
+      assert %{"access_token" => token, "refresh_token" => refresh, "scope" => scope} =
+               json_response(conn, 200)
+
+      assert token
+      token_from_db = Repo.get_by(Token, token: token)
+      assert token_from_db
+      assert refresh
+      assert scope == "read write follow"
+
+      conn =
+        build_conn()
+        |> put_req_header("content-type", "multipart/form-data")
+        |> put_req_header("authorization", "Bearer " <> token)
+        |> post("/api/v1/accounts", %{
+          username: "lain",
+          email: "lain@example.org",
+          password: "PlzDontHackLain",
+          bio: "Test Bio",
+          agreement: true,
+          reason: "I'm a cool dude, bro"
+        })
+
+      %{
+        "access_token" => token,
+        "created_at" => _created_at,
+        "scope" => ^scope,
+        "token_type" => "Bearer"
+      } = json_response_and_validate_schema(conn, 200)
+
+      token_from_db = Repo.get_by(Token, token: token)
+      assert token_from_db
+      token_from_db = Repo.preload(token_from_db, :user)
+      assert token_from_db.user
+
+      assert token_from_db.user.confirmation_pending
+      assert token_from_db.user.approval_pending
+
+      assert token_from_db.user.registration_reason == "I'm a cool dude, bro"
+    end
+
     test "returns error when user already registred", %{conn: conn, valid_params: valid_params} do
       _user = insert(:user, email: "lain@example.org")
       app_token = insert(:oauth_token, user: nil)
diff --git a/test/web/mastodon_api/controllers/instance_controller_test.exs b/test/web/mastodon_api/controllers/instance_controller_test.exs
index cc880d82c..6a9ccd979 100644
--- a/test/web/mastodon_api/controllers/instance_controller_test.exs
+++ b/test/web/mastodon_api/controllers/instance_controller_test.exs
@@ -27,6 +27,7 @@ defmodule Pleroma.Web.MastodonAPI.InstanceControllerTest do
              "thumbnail" => _,
              "languages" => _,
              "registrations" => _,
+             "approval_required" => _,
              "poll_limits" => _,
              "upload_limit" => _,
              "avatar_upload_limit" => _,
diff --git a/test/web/oauth/oauth_controller_test.exs b/test/web/oauth/oauth_controller_test.exs
index d389e4ce0..1200126b8 100644
--- a/test/web/oauth/oauth_controller_test.exs
+++ b/test/web/oauth/oauth_controller_test.exs
@@ -19,7 +19,10 @@ defmodule Pleroma.Web.OAuth.OAuthControllerTest do
     key: "_test",
     signing_salt: "cooldude"
   ]
-  setup do: clear_config([:instance, :account_activation_required])
+  setup do
+    clear_config([:instance, :account_activation_required])
+    clear_config([:instance, :account_approval_required])
+  end
 
   describe "in OAuth consumer mode, " do
     setup do
@@ -995,6 +998,30 @@ defmodule Pleroma.Web.OAuth.OAuthControllerTest do
              }
     end
 
+    test "rejects token exchange for valid credentials belonging to an unapproved user" do
+      password = "testpassword"
+
+      user = insert(:user, password_hash: Pbkdf2.hash_pwd_salt(password), approval_pending: true)
+
+      refute Pleroma.User.account_status(user) == :active
+
+      app = insert(:oauth_app)
+
+      conn =
+        build_conn()
+        |> post("/oauth/token", %{
+          "grant_type" => "password",
+          "username" => user.nickname,
+          "password" => password,
+          "client_id" => app.client_id,
+          "client_secret" => app.client_secret
+        })
+
+      assert resp = json_response(conn, 403)
+      assert %{"error" => _} = resp
+      refute Map.has_key?(resp, "access_token")
+    end
+
     test "rejects an invalid authorization code" do
       app = insert(:oauth_app)
 
diff --git a/test/web/twitter_api/twitter_api_test.exs b/test/web/twitter_api/twitter_api_test.exs
index 5bb2d8d89..20a45cb6f 100644
--- a/test/web/twitter_api/twitter_api_test.exs
+++ b/test/web/twitter_api/twitter_api_test.exs
@@ -4,7 +4,7 @@
 
 defmodule Pleroma.Web.TwitterAPI.TwitterAPITest do
   use Pleroma.DataCase
-
+  import Pleroma.Factory
   alias Pleroma.Repo
   alias Pleroma.Tests.ObanHelpers
   alias Pleroma.User
@@ -79,6 +79,42 @@ defmodule Pleroma.Web.TwitterAPI.TwitterAPITest do
     )
   end
 
+  test "it sends an admin email if :account_approval_required is specified in instance config" do
+    admin = insert(:user, is_admin: true)
+    setting = Pleroma.Config.get([:instance, :account_approval_required])
+
+    unless setting do
+      Pleroma.Config.put([:instance, :account_approval_required], true)
+      on_exit(fn -> Pleroma.Config.put([:instance, :account_approval_required], setting) end)
+    end
+
+    data = %{
+      :username => "lain",
+      :email => "lain@wired.jp",
+      :fullname => "lain iwakura",
+      :bio => "",
+      :password => "bear",
+      :confirm => "bear",
+      :reason => "I love anime"
+    }
+
+    {:ok, user} = TwitterAPI.register_user(data)
+    ObanHelpers.perform_all()
+
+    assert user.approval_pending
+
+    email = Pleroma.Emails.AdminEmail.new_unapproved_registration(admin, user)
+
+    notify_email = Pleroma.Config.get([:instance, :notify_email])
+    instance_name = Pleroma.Config.get([:instance, :name])
+
+    Swoosh.TestAssertions.assert_email_sent(
+      from: {instance_name, notify_email},
+      to: {admin.name, admin.email},
+      html_body: email.html_body
+    )
+  end
+
   test "it registers a new user and parses mentions in the bio" do
     data1 = %{
       :username => "john",