Merge branch 'tusooa/quote' into 'develop'

Quoting

See merge request pleroma/pleroma!3921

38 files changed, 1240 insertions, 12 deletions

diff --git a/changelog.d/quote.add b/changelog.d/quote.add
new file mode 100644
index 000000000..1c368ae75
--- /dev/null
+++ b/changelog.d/quote.add
@@ -0,0 +1 @@
+Implement quotes
diff --git a/config/config.exs b/config/config.exs
index ebcbf8b49..e8ae31542 100644
--- a/config/config.exs
+++ b/config/config.exs
@@ -434,6 +434,8 @@ config :pleroma, :mrf_object_age,
 
 config :pleroma, :mrf_follow_bot, follower_nickname: nil
 
+config :pleroma, :mrf_inline_quote, template: "<bdi>RT:</bdi> {url}"
+
 config :pleroma, :rich_media,
   enabled: true,
   ignore_hosts: [],
@@ -858,7 +860,11 @@ config :pleroma, :restrict_unauthenticated,
 config :pleroma, Pleroma.Web.ApiSpec.CastAndValidate, strict: false
 
 config :pleroma, :mrf,
-  policies: [Pleroma.Web.ActivityPub.MRF.ObjectAgePolicy, Pleroma.Web.ActivityPub.MRF.TagPolicy],
+  policies: [
+    Pleroma.Web.ActivityPub.MRF.ObjectAgePolicy,
+    Pleroma.Web.ActivityPub.MRF.TagPolicy,
+    Pleroma.Web.ActivityPub.MRF.InlineQuotePolicy
+  ],
   transparency: true,
   transparency_exclusions: []
 
diff --git a/docs/configuration/cheatsheet.md b/docs/configuration/cheatsheet.md
index f43cde114..a4cae4dbb 100644
--- a/docs/configuration/cheatsheet.md
+++ b/docs/configuration/cheatsheet.md
@@ -160,6 +160,8 @@ To add configuration to your config file, you can copy it from the base config.
     * `Pleroma.Web.ActivityPub.MRF.AntiFollowbotPolicy`: Drops follow requests from followbots. Users can still allow bots to follow them by first following the bot.
     * `Pleroma.Web.ActivityPub.MRF.KeywordPolicy`: Rejects or removes from the federated timeline or replaces keywords. (See [`:mrf_keyword`](#mrf_keyword)).
     * `Pleroma.Web.ActivityPub.MRF.ForceMentionsInContent`: Forces every mentioned user to be reflected in the post content.
+    * `Pleroma.Web.ActivityPub.MRF.InlineQuotePolicy`: Forces quote post URLs to be reflected in the message content inline.
+    * `Pleroma.Web.ActivityPub.MRF.QuoteToLinkTagPolicy`: Force a Link tag for posts quoting another post. (may break outgoing federation of quote posts with older Pleroma versions)
 * `transparency`: Make the content of your Message Rewrite Facility settings public (via nodeinfo).
 * `transparency_exclusions`: Exclude specific instance names from MRF transparency.  The use of the exclusions feature will be disclosed in nodeinfo as a boolean value.
 
@@ -267,6 +269,9 @@ Notes:
 * `federated_timeline_removal_url`: A list of patterns which result in message with emojis whose URLs match being removed from federated timelines (a.k.a unlisted). This will apply only to statuses. Each pattern can be a string or a [regular expression](https://hexdocs.pm/elixir/Regex.html).
 * `federated_timeline_removal_shortcode`: A list of patterns which result in message with emojis whose shortcodes match being removed from federated timelines (a.k.a unlisted). This will apply only to statuses. Each pattern can be a string or a [regular expression](https://hexdocs.pm/elixir/Regex.html).
 
+#### :mrf_inline_quote
+* `template`: The template to append to the post. `{url}` will be replaced with the actual link to the quoted post. Default: `<bdi>RT:</bdi> {url}`
+
 ### :activitypub
 * `unfollow_blocked`: Whether blocks result in people getting unfollowed
 * `outgoing_blocks`: Whether to federate blocks to other instances
diff --git a/lib/pleroma/constants.ex b/lib/pleroma/constants.ex
index 6befc6897..ed60bcc37 100644
--- a/lib/pleroma/constants.ex
+++ b/lib/pleroma/constants.ex
@@ -83,4 +83,15 @@ defmodule Pleroma.Constants do
   )
 
   const(upload_object_types, do: ["Document", "Image"])
+
+  const(activity_json_canonical_mime_type,
+    do: "application/ld+json; profile=\"https://www.w3.org/ns/activitystreams\""
+  )
+
+  const(activity_json_mime_types,
+    do: [
+      "application/ld+json; profile=\"https://www.w3.org/ns/activitystreams\"",
+      "application/activity+json"
+    ]
+  )
 end
diff --git a/lib/pleroma/web/activity_pub/builder.ex b/lib/pleroma/web/activity_pub/builder.ex
index 8eab3a241..eb0bb0e33 100644
--- a/lib/pleroma/web/activity_pub/builder.ex
+++ b/lib/pleroma/web/activity_pub/builder.ex
@@ -217,6 +217,7 @@ defmodule Pleroma.Web.ActivityPub.Builder do
         "tag" => Keyword.values(draft.tags) |> Enum.uniq()
       }
       |> add_in_reply_to(draft.in_reply_to)
+      |> add_quote(draft.quote_post)
       |> Map.merge(draft.extra)
 
     {:ok, data, []}
@@ -232,6 +233,16 @@ defmodule Pleroma.Web.ActivityPub.Builder do
     end
   end
 
+  defp add_quote(object, nil), do: object
+
+  defp add_quote(object, quote_post) do
+    with %Object{} = quote_object <- Object.normalize(quote_post, fetch: false) do
+      Map.put(object, "quoteUrl", quote_object.data["id"])
+    else
+      _ -> object
+    end
+  end
+
   def chat_message(actor, recipient, content, opts \\ []) do
     basic = %{
       "id" => Utils.generate_object_id(),
diff --git a/lib/pleroma/web/activity_pub/mrf/inline_quote_policy.ex b/lib/pleroma/web/activity_pub/mrf/inline_quote_policy.ex
new file mode 100644
index 000000000..171b22c5e
--- /dev/null
+++ b/lib/pleroma/web/activity_pub/mrf/inline_quote_policy.ex
@@ -0,0 +1,78 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Web.ActivityPub.MRF.InlineQuotePolicy do
+  @moduledoc "Force a quote line into the message content."
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
+  defp build_inline_quote(template, url) do
+    quote_line = String.replace(template, "{url}", "<a href=\"#{url}\">#{url}</a>")
+
+    "<span class=\"quote-inline\"><br/><br/>#{quote_line}</span>"
+  end
+
+  defp has_inline_quote?(content, quote_url) do
+    cond do
+      # Does the quote URL exist in the content?
+      content =~ quote_url -> true
+      # Does the content already have a .quote-inline span?
+      content =~ "<span class=\"quote-inline\">" -> true
+      # No inline quote found
+      true -> false
+    end
+  end
+
+  defp filter_object(%{"quoteUrl" => quote_url} = object) do
+    content = object["content"] || ""
+
+    if has_inline_quote?(content, quote_url) do
+      object
+    else
+      template = Pleroma.Config.get([:mrf_inline_quote, :template])
+
+      content =
+        if String.ends_with?(content, "</p>"),
+          do:
+            String.trim_trailing(content, "</p>") <>
+              build_inline_quote(template, quote_url) <> "</p>",
+          else: content <> build_inline_quote(template, quote_url)
+
+      Map.put(object, "content", content)
+    end
+  end
+
+  @impl true
+  def filter(%{"object" => %{"quoteUrl" => _} = object} = activity) do
+    {:ok, Map.put(activity, "object", filter_object(object))}
+  end
+
+  @impl true
+  def filter(object), do: {:ok, object}
+
+  @impl true
+  def describe, do: {:ok, %{}}
+
+  @impl Pleroma.Web.ActivityPub.MRF.Policy
+  def history_awareness, do: :auto
+
+  @impl true
+  def config_description do
+    %{
+      key: :mrf_inline_quote,
+      related_policy: "Pleroma.Web.ActivityPub.MRF.InlineQuotePolicy",
+      label: "MRF Inline Quote Policy",
+      type: :group,
+      description: "Force quote url to appear in post content.",
+      children: [
+        %{
+          key: :template,
+          type: :string,
+          description:
+            "The template to append to the post. `{url}` will be replaced with the actual link to the quoted post.",
+          suggestions: ["<bdi>RT:</bdi> {url}"]
+        }
+      ]
+    }
+  end
+end
diff --git a/lib/pleroma/web/activity_pub/mrf/quote_to_link_tag_policy.ex b/lib/pleroma/web/activity_pub/mrf/quote_to_link_tag_policy.ex
new file mode 100644
index 000000000..f1c573d1b
--- /dev/null
+++ b/lib/pleroma/web/activity_pub/mrf/quote_to_link_tag_policy.ex
@@ -0,0 +1,49 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2023 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Web.ActivityPub.MRF.QuoteToLinkTagPolicy do
+  @moduledoc "Force a Link tag for posts quoting another post. (may break outgoing federation of quote posts with older Pleroma versions)"
+  @behaviour Pleroma.Web.ActivityPub.MRF.Policy
+
+  alias Pleroma.Web.ActivityPub.ObjectValidators.CommonFixes
+
+  require Pleroma.Constants
+
+  @impl Pleroma.Web.ActivityPub.MRF.Policy
+  def filter(%{"object" => %{"quoteUrl" => _} = object} = activity) do
+    {:ok, Map.put(activity, "object", filter_object(object))}
+  end
+
+  @impl Pleroma.Web.ActivityPub.MRF.Policy
+  def filter(object), do: {:ok, object}
+
+  @impl Pleroma.Web.ActivityPub.MRF.Policy
+  def describe, do: {:ok, %{}}
+
+  @impl Pleroma.Web.ActivityPub.MRF.Policy
+  def history_awareness, do: :auto
+
+  defp filter_object(%{"quoteUrl" => quote_url} = object) do
+    tags = object["tag"] || []
+
+    if Enum.any?(tags, fn tag ->
+         CommonFixes.is_object_link_tag(tag) and tag["href"] == quote_url
+       end) do
+      object
+    else
+      object
+      |> Map.put(
+        "tag",
+        tags ++
+          [
+            %{
+              "type" => "Link",
+              "mediaType" => Pleroma.Constants.activity_json_canonical_mime_type(),
+              "href" => quote_url
+            }
+          ]
+      )
+    end
+  end
+end
diff --git a/lib/pleroma/web/activity_pub/object_validators/article_note_page_validator.ex b/lib/pleroma/web/activity_pub/object_validators/article_note_page_validator.ex
index 2670e3f17..1b5b2e8fb 100644
--- a/lib/pleroma/web/activity_pub/object_validators/article_note_page_validator.ex
+++ b/lib/pleroma/web/activity_pub/object_validators/article_note_page_validator.ex
@@ -84,6 +84,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.ArticleNotePageValidator do
     |> fix_tag()
     |> fix_replies()
     |> fix_attachments()
+    |> CommonFixes.fix_quote_url()
     |> Transmogrifier.fix_emoji()
     |> Transmogrifier.fix_content_map()
   end
diff --git a/lib/pleroma/web/activity_pub/object_validators/audio_image_video_validator.ex b/lib/pleroma/web/activity_pub/object_validators/audio_image_video_validator.ex
index 79ff76104..65ac6bb93 100644
--- a/lib/pleroma/web/activity_pub/object_validators/audio_image_video_validator.ex
+++ b/lib/pleroma/web/activity_pub/object_validators/audio_image_video_validator.ex
@@ -99,6 +99,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.AudioImageVideoValidator do
     data
     |> CommonFixes.fix_actor()
     |> CommonFixes.fix_object_defaults()
+    |> CommonFixes.fix_quote_url()
     |> Transmogrifier.fix_emoji()
     |> fix_url()
     |> fix_content()
diff --git a/lib/pleroma/web/activity_pub/object_validators/common_fields.ex b/lib/pleroma/web/activity_pub/object_validators/common_fields.ex
index d580208df..835ed97b7 100644
--- a/lib/pleroma/web/activity_pub/object_validators/common_fields.ex
+++ b/lib/pleroma/web/activity_pub/object_validators/common_fields.ex
@@ -27,7 +27,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.CommonFields do
     end
   end
 
-  # All objects except Answer and CHatMessage
+  # All objects except Answer and ChatMessage
   defmacro object_fields do
     quote bind_quoted: binding() do
       field(:content, :string)
@@ -58,6 +58,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.CommonFields do
       field(:like_count, :integer, default: 0)
       field(:announcement_count, :integer, default: 0)
       field(:inReplyTo, ObjectValidators.ObjectID)
+      field(:quoteUrl, ObjectValidators.ObjectID)
       field(:url, ObjectValidators.BareUri)
 
       field(:likes, {:array, ObjectValidators.ObjectID}, default: [])
diff --git a/lib/pleroma/web/activity_pub/object_validators/common_fixes.ex b/lib/pleroma/web/activity_pub/object_validators/common_fixes.ex
index add46d561..4d9be0bdd 100644
--- a/lib/pleroma/web/activity_pub/object_validators/common_fixes.ex
+++ b/lib/pleroma/web/activity_pub/object_validators/common_fixes.ex
@@ -10,6 +10,8 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.CommonFixes do
   alias Pleroma.Web.ActivityPub.Transmogrifier
   alias Pleroma.Web.ActivityPub.Utils
 
+  require Pleroma.Constants
+
   def cast_and_filter_recipients(message, field, follower_collection, field_fallback \\ []) do
     {:ok, data} = ObjectValidators.Recipients.cast(message[field] || field_fallback)
 
@@ -76,4 +78,48 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.CommonFixes do
 
     Map.put(data, "to", to)
   end
+
+  def fix_quote_url(%{"quoteUrl" => _quote_url} = data), do: data
+
+  # Fedibird
+  # https://github.com/fedibird/mastodon/commit/dbd7ae6cf58a92ec67c512296b4daaea0d01e6ac
+  def fix_quote_url(%{"quoteUri" => quote_url} = data) do
+    Map.put(data, "quoteUrl", quote_url)
+  end
+
+  # Old Fedibird (bug)
+  # https://github.com/fedibird/mastodon/issues/9
+  def fix_quote_url(%{"quoteURL" => quote_url} = data) do
+    Map.put(data, "quoteUrl", quote_url)
+  end
+
+  # Misskey fallback
+  def fix_quote_url(%{"_misskey_quote" => quote_url} = data) do
+    Map.put(data, "quoteUrl", quote_url)
+  end
+
+  def fix_quote_url(%{"tag" => [_ | _] = tags} = data) do
+    tag = Enum.find(tags, &is_object_link_tag/1)
+
+    if not is_nil(tag) do
+      data
+      |> Map.put("quoteUrl", tag["href"])
+    else
+      data
+    end
+  end
+
+  def fix_quote_url(data), do: data
+
+  # https://codeberg.org/fediverse/fep/src/branch/main/fep/e232/fep-e232.md
+  def is_object_link_tag(%{
+        "type" => "Link",
+        "mediaType" => media_type,
+        "href" => href
+      })
+      when media_type in Pleroma.Constants.activity_json_mime_types() and is_binary(href) do
+    true
+  end
+
+  def is_object_link_tag(_), do: false
 end
diff --git a/lib/pleroma/web/activity_pub/object_validators/question_validator.ex b/lib/pleroma/web/activity_pub/object_validators/question_validator.ex
index ce3305142..621085e6c 100644
--- a/lib/pleroma/web/activity_pub/object_validators/question_validator.ex
+++ b/lib/pleroma/web/activity_pub/object_validators/question_validator.ex
@@ -62,6 +62,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.QuestionValidator do
     data
     |> CommonFixes.fix_actor()
     |> CommonFixes.fix_object_defaults()
+    |> CommonFixes.fix_quote_url()
     |> Transmogrifier.fix_emoji()
     |> fix_closed()
   end
diff --git a/lib/pleroma/web/activity_pub/object_validators/tag_validator.ex b/lib/pleroma/web/activity_pub/object_validators/tag_validator.ex
index cfd510c19..47cf7b415 100644
--- a/lib/pleroma/web/activity_pub/object_validators/tag_validator.ex
+++ b/lib/pleroma/web/activity_pub/object_validators/tag_validator.ex
@@ -9,15 +9,20 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.TagValidator do
 
   import Ecto.Changeset
 
+  require Pleroma.Constants
+
   @primary_key false
   embedded_schema do
     # Common
     field(:type, :string)
     field(:name, :string)
 
-    # Mention, Hashtag
+    # Mention, Hashtag, Link
     field(:href, ObjectValidators.Uri)
 
+    # Link
+    field(:mediaType, :string)
+
     # Emoji
     embeds_one :icon, IconObjectValidator, primary_key: false do
       field(:type, :string)
@@ -68,6 +73,13 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.TagValidator do
     |> validate_required([:type, :name, :icon])
   end
 
+  def changeset(struct, %{"type" => "Link"} = data) do
+    struct
+    |> cast(data, [:type, :name, :mediaType, :href])
+    |> validate_inclusion(:mediaType, Pleroma.Constants.activity_json_mime_types())
+    |> validate_required([:type, :href, :mediaType])
+  end
+
   def changeset(struct, %{"type" => _} = data) do
     struct
     |> cast(data, [])
diff --git a/lib/pleroma/web/activity_pub/transmogrifier.ex b/lib/pleroma/web/activity_pub/transmogrifier.ex
index 0e6c429f9..86d3ac60f 100644
--- a/lib/pleroma/web/activity_pub/transmogrifier.ex
+++ b/lib/pleroma/web/activity_pub/transmogrifier.ex
@@ -166,6 +166,27 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
 
   def fix_in_reply_to(object, _options), do: object
 
+  def fix_quote_url_and_maybe_fetch(object, options \\ []) do
+    quote_url =
+      case Pleroma.Web.ActivityPub.ObjectValidators.CommonFixes.fix_quote_url(object) do
+        %{"quoteUrl" => quote_url} -> quote_url
+        _ -> nil
+      end
+
+    with {:quoting?, true} <- {:quoting?, not is_nil(quote_url)},
+         {:ok, quoted_object} <- get_obj_helper(quote_url, options),
+         %Activity{} <- Activity.get_create_by_object_ap_id(quoted_object.data["id"]) do
+      Map.put(object, "quoteUrl", quoted_object.data["id"])
+    else
+      {:quoting?, _} ->
+        object
+
+      e ->
+        Logger.warn("Couldn't fetch #{inspect(quote_url)}, error: #{inspect(e)}")
+        object
+    end
+  end
+
   defp prepare_in_reply_to(in_reply_to) do
     cond do
       is_bitstring(in_reply_to) ->
@@ -454,6 +475,7 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
       |> strip_internal_fields()
       |> fix_type(fetch_options)
       |> fix_in_reply_to(fetch_options)
+      |> fix_quote_url_and_maybe_fetch(fetch_options)
 
     data = Map.put(data, "object", object)
     options = Keyword.put(options, :local, false)
@@ -629,6 +651,16 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
   def set_reply_to_uri(obj), do: obj
 
   @doc """
+  Fedibird compatibility
+  https://github.com/fedibird/mastodon/commit/dbd7ae6cf58a92ec67c512296b4daaea0d01e6ac
+  """
+  def set_quote_url(%{"quoteUrl" => quote_url} = object) when is_binary(quote_url) do
+    Map.put(object, "quoteUri", quote_url)
+  end
+
+  def set_quote_url(obj), do: obj
+
+  @doc """
   Serialized Mastodon-compatible `replies` collection containing _self-replies_.
   Based on Mastodon's ActivityPub::NoteSerializer#replies.
   """
@@ -682,6 +714,7 @@ defmodule Pleroma.Web.ActivityPub.Transmogrifier do
     |> prepare_attachments
     |> set_conversation
     |> set_reply_to_uri
+    |> set_quote_url
     |> set_replies
     |> strip_internal_fields
     |> strip_internal_tags
diff --git a/lib/pleroma/web/api_spec/operations/status_operation.ex b/lib/pleroma/web/api_spec/operations/status_operation.ex
index 5d6e82f3c..c133a3aac 100644
--- a/lib/pleroma/web/api_spec/operations/status_operation.ex
+++ b/lib/pleroma/web/api_spec/operations/status_operation.ex
@@ -581,6 +581,11 @@ defmodule Pleroma.Web.ApiSpec.StatusOperation do
           type: :string,
           description:
             "Will reply to a given conversation, addressing only the people who are part of the recipient set of that conversation. Sets the visibility to `direct`."
+        },
+        quote_id: %Schema{
+          nullable: true,
+          allOf: [FlakeID],
+          description: "ID of the status being quoted, if any"
         }
       },
       example: %{
diff --git a/lib/pleroma/web/api_spec/schemas/status.ex b/lib/pleroma/web/api_spec/schemas/status.ex
index bc29cf4a6..07f03134a 100644
--- a/lib/pleroma/web/api_spec/schemas/status.ex
+++ b/lib/pleroma/web/api_spec/schemas/status.ex
@@ -193,6 +193,26 @@ defmodule Pleroma.Web.ApiSpec.Schemas.Status do
             nullable: true,
             description: "The `acct` property of User entity for replied user (if any)"
           },
+          quote: %Schema{
+            allOf: [%OpenApiSpex.Reference{"$ref": "#/components/schemas/Status"}],
+            nullable: true,
+            description: "Quoted status (if any)"
+          },
+          quote_id: %Schema{
+            nullable: true,
+            allOf: [FlakeID],
+            description: "ID of the status being quoted, if any"
+          },
+          quote_url: %Schema{
+            type: :string,
+            format: :uri,
+            nullable: true,
+            description: "URL of the quoted status"
+          },
+          quote_visible: %Schema{
+            type: :boolean,
+            description: "`true` if the quoted post is visible to the user"
+          },
           local: %Schema{
             type: :boolean,
             description: "`true` if the post was made on the local instance"
diff --git a/lib/pleroma/web/common_api/activity_draft.ex b/lib/pleroma/web/common_api/activity_draft.ex
index 63ed48a27..ca1329284 100644
--- a/lib/pleroma/web/common_api/activity_draft.ex
+++ b/lib/pleroma/web/common_api/activity_draft.ex
@@ -7,10 +7,12 @@ defmodule Pleroma.Web.CommonAPI.ActivityDraft do
   alias Pleroma.Conversation.Participation
   alias Pleroma.Object
   alias Pleroma.Web.ActivityPub.Builder
+  alias Pleroma.Web.ActivityPub.Visibility
   alias Pleroma.Web.CommonAPI
   alias Pleroma.Web.CommonAPI.Utils
 
   import Pleroma.Web.Gettext
+  import Pleroma.Web.Utils.Guards, only: [not_empty_string: 1]
 
   defstruct valid?: true,
             errors: [],
@@ -22,6 +24,7 @@ defmodule Pleroma.Web.CommonAPI.ActivityDraft do
             attachments: [],
             in_reply_to: nil,
             in_reply_to_conversation: nil,
+            quote_post: nil,
             visibility: nil,
             expires_at: nil,
             extra: nil,
@@ -53,7 +56,9 @@ defmodule Pleroma.Web.CommonAPI.ActivityDraft do
     |> poll()
     |> with_valid(&in_reply_to/1)
     |> with_valid(&in_reply_to_conversation/1)
+    |> with_valid(&quote_post/1)
     |> with_valid(&visibility/1)
+    |> with_valid(&quoting_visibility/1)
     |> content()
     |> with_valid(&to_and_cc/1)
     |> with_valid(&context/1)
@@ -132,6 +137,18 @@ defmodule Pleroma.Web.CommonAPI.ActivityDraft do
 
   defp in_reply_to(draft), do: draft
 
+  defp quote_post(%{params: %{quote_id: id}} = draft) when not_empty_string(id) do
+    case Activity.get_by_id_with_object(id) do
+      %Activity{} = activity ->
+        %__MODULE__{draft | quote_post: activity}
+
+      _ ->
+        draft
+    end
+  end
+
+  defp quote_post(draft), do: draft
+
   defp in_reply_to_conversation(draft) do
     in_reply_to_conversation = Participation.get(draft.params[:in_reply_to_conversation_id])
     %__MODULE__{draft | in_reply_to_conversation: in_reply_to_conversation}
@@ -147,6 +164,29 @@ defmodule Pleroma.Web.CommonAPI.ActivityDraft do
     end
   end
 
+  defp can_quote?(_draft, _object, visibility) when visibility in ~w(public unlisted local) do
+    true
+  end
+
+  defp can_quote?(draft, object, "private") do
+    draft.user.ap_id == object.data["actor"]
+  end
+
+  defp can_quote?(_, _, _) do
+    false
+  end
+
+  defp quoting_visibility(%{quote_post: %Activity{}} = draft) do
+    with %Object{} = object <- Object.normalize(draft.quote_post, fetch: false),
+         true <- can_quote?(draft, object, Visibility.get_visibility(object)) do
+      draft
+    else
+      _ -> add_error(draft, dgettext("errors", "Cannot quote private message"))
+    end
+  end
+
+  defp quoting_visibility(draft), do: draft
+
   defp expires_at(draft) do
     case CommonAPI.check_expiry_date(draft.params[:expires_in]) do
       {:ok, expires_at} -> %__MODULE__{draft | expires_at: expires_at}
@@ -164,12 +204,15 @@ defmodule Pleroma.Web.CommonAPI.ActivityDraft do
     end
   end
 
-  defp content(draft) do
+  defp content(%{mentions: mentions} = draft) do
     {content_html, mentioned_users, tags} = Utils.make_content_html(draft)
 
+    mentioned_ap_ids =
+      Enum.map(mentioned_users, fn {_, mentioned_user} -> mentioned_user.ap_id end)
+
     mentions =
-      mentioned_users
-      |> Enum.map(fn {_, mentioned_user} -> mentioned_user.ap_id end)
+      mentions
+      |> Kernel.++(mentioned_ap_ids)
       |> Utils.get_addressed_users(draft.params[:to])
 
     %__MODULE__{draft | content_html: content_html, mentions: mentions, tags: tags}
diff --git a/lib/pleroma/web/mastodon_api/views/instance_view.ex b/lib/pleroma/web/mastodon_api/views/instance_view.ex
index efd2a0af6..1b01d7371 100644
--- a/lib/pleroma/web/mastodon_api/views/instance_view.ex
+++ b/lib/pleroma/web/mastodon_api/views/instance_view.ex
@@ -69,6 +69,7 @@ defmodule Pleroma.Web.MastodonAPI.InstanceView do
       "multifetch",
       "pleroma:api/v1/notifications:include_types_filter",
       "editing",
+      "quote_posting",
       if Config.get([:activitypub, :blockers_visible]) do
         "blockers_visible"
       end,
diff --git a/lib/pleroma/web/mastodon_api/views/status_view.ex b/lib/pleroma/web/mastodon_api/views/status_view.ex
index dea22f9c2..d070262cc 100644
--- a/lib/pleroma/web/mastodon_api/views/status_view.ex
+++ b/lib/pleroma/web/mastodon_api/views/status_view.ex
@@ -57,6 +57,27 @@ defmodule Pleroma.Web.MastodonAPI.StatusView do
     end)
   end
 
+  defp get_quoted_activities([]), do: %{}
+
+  defp get_quoted_activities(activities) do
+    activities
+    |> Enum.map(fn
+      %{data: %{"type" => "Create"}} = activity ->
+        object = Object.normalize(activity, fetch: false)
+        object && object.data["quoteUrl"] != "" && object.data["quoteUrl"]
+
+      _ ->
+        nil
+    end)
+    |> Enum.filter(& &1)
+    |> Activity.create_by_object_ap_id_with_object()
+    |> Repo.all()
+    |> Enum.reduce(%{}, fn activity, acc ->
+      object = Object.normalize(activity, fetch: false)
+      if object, do: Map.put(acc, object.data["id"], activity), else: acc
+    end)
+  end
+
   # DEPRECATED This field seems to be a left-over from the StatusNet era.
   # If your application uses `pleroma.conversation_id`: this field is deprecated.
   # It is currently stubbed instead by doing a CRC32 of the context, and
@@ -97,6 +118,7 @@ defmodule Pleroma.Web.MastodonAPI.StatusView do
     # length(activities_with_links) * timeout
     fetch_rich_media_for_activities(activities)
     replied_to_activities = get_replied_to_activities(activities)
+    quoted_activities = get_quoted_activities(activities)
 
     parent_activities =
       activities
@@ -129,6 +151,7 @@ defmodule Pleroma.Web.MastodonAPI.StatusView do
     opts =
       opts
       |> Map.put(:replied_to_activities, replied_to_activities)
+      |> Map.put(:quoted_activities, quoted_activities)
       |> Map.put(:parent_activities, parent_activities)
       |> Map.put(:relationships, relationships_opt)
 
@@ -277,7 +300,6 @@ defmodule Pleroma.Web.MastodonAPI.StatusView do
       end
 
     reply_to = get_reply_to(activity, opts)
-
     reply_to_user = reply_to && CommonAPI.get_user(reply_to.data["actor"])
 
     history_len =
@@ -290,6 +312,22 @@ defmodule Pleroma.Web.MastodonAPI.StatusView do
     # Here the implicit index of the current content is 0
     chrono_order = history_len - 1
 
+    quote_activity = get_quote(activity, opts)
+
+    quote_id =
+      case quote_activity do
+        %Activity{id: id} -> id
+        _ -> nil
+      end
+
+    quote_post =
+      if visible_for_user?(quote_activity, opts[:for]) and opts[:show_quote] != false do
+        quote_rendering_opts = Map.merge(opts, %{activity: quote_activity, show_quote: false})
+        render("show.json", quote_rendering_opts)
+      else
+        nil
+      end
+
     content =
       object
       |> render_content()
@@ -398,6 +436,10 @@ defmodule Pleroma.Web.MastodonAPI.StatusView do
         conversation_id: get_context_id(activity),
         context: object.data["context"],
         in_reply_to_account_acct: reply_to_user && reply_to_user.nickname,
+        quote: quote_post,
+        quote_id: quote_id,
+        quote_url: object.data["quoteUrl"],
+        quote_visible: visible_for_user?(quote_activity, opts[:for]),
         content: %{"text/plain" => content_plaintext},
         spoiler_text: %{"text/plain" => summary},
         expires_at: expires_at,
@@ -633,6 +675,25 @@ defmodule Pleroma.Web.MastodonAPI.StatusView do
     end
   end
 
+  def get_quote(activity, %{quoted_activities: quoted_activities}) do
+    object = Object.normalize(activity, fetch: false)
+
+    with nil <- quoted_activities[object.data["quoteUrl"]] do
+      # For when a quote post is inside an Announce
+      Activity.get_create_by_object_ap_id_with_object(object.data["quoteUrl"])
+    end
+  end
+
+  def get_quote(%{data: %{"object" => _object}} = activity, _) do
+    object = Object.normalize(activity, fetch: false)
+
+    if object.data["quoteUrl"] && object.data["quoteUrl"] != "" do
+      Activity.get_create_by_object_ap_id(object.data["quoteUrl"])
+    else
+      nil
+    end
+  end
+
   def render_content(%{data: %{"name" => name}} = object) when not is_nil(name) and name != "" do
     url = object.data["url"] || object.data["id"]
 
diff --git a/priv/scrubbers/default.ex b/priv/scrubbers/default.ex
index d1215d2e0..24a76263b 100644
--- a/priv/scrubbers/default.ex
+++ b/priv/scrubbers/default.ex
@@ -38,6 +38,7 @@ defmodule Pleroma.HTML.Scrubber.Default do
   Meta.allow_tag_with_these_attributes(:abbr, ["title", "lang"])
 
   Meta.allow_tag_with_these_attributes(:b, ["lang"])
+  Meta.allow_tag_with_these_attributes(:bdi, [])
   Meta.allow_tag_with_these_attributes(:blockquote, ["lang"])
   Meta.allow_tag_with_these_attributes(:br, ["lang"])
   Meta.allow_tag_with_these_attributes(:code, ["lang"])
@@ -60,7 +61,12 @@ defmodule Pleroma.HTML.Scrubber.Default do
   Meta.allow_tag_with_these_attributes(:u, ["lang"])
   Meta.allow_tag_with_these_attributes(:ul, ["lang"])
 
-  Meta.allow_tag_with_this_attribute_values(:span, "class", ["h-card", "recipients-inline"])
+  Meta.allow_tag_with_this_attribute_values(:span, "class", [
+    "h-card",
+    "recipients-inline",
+    "quote-inline"
+  ])
+
   Meta.allow_tag_with_these_attributes(:span, ["lang"])
 
   Meta.allow_tag_with_this_attribute_values(:code, "class", ["inline"])
diff --git a/priv/static/schemas/litepub-0.1.jsonld b/priv/static/schemas/litepub-0.1.jsonld
index 650118475..b499a96f5 100644
--- a/priv/static/schemas/litepub-0.1.jsonld
+++ b/priv/static/schemas/litepub-0.1.jsonld
@@ -17,6 +17,7 @@
             "ostatus": "http://ostatus.org#",
             "schema": "http://schema.org#",
             "toot": "http://joinmastodon.org/ns#",
+            "fedibird": "http://fedibird.com/ns#",
             "value": "schema:value",
             "sensitive": "as:sensitive",
             "litepub": "http://litepub.social/ns#",
@@ -26,6 +27,8 @@
                 "@id": "litepub:listMessage",
                 "@type": "@id"
             },
+            "quoteUrl": "as:quoteUrl",
+            "quoteUri": "fedibird:quoteUri",
             "oauthRegistrationEndpoint": {
                 "@id": "litepub:oauthRegistrationEndpoint",
                 "@type": "@id"
diff --git a/test/fixtures/quote_post/fedibird_quote_mismatched.json b/test/fixtures/quote_post/fedibird_quote_mismatched.json
new file mode 100644
index 000000000..8dee5daff
--- /dev/null
+++ b/test/fixtures/quote_post/fedibird_quote_mismatched.json
@@ -0,0 +1,54 @@
+{
+  "@context": [
+    "https://www.w3.org/ns/activitystreams",
+    {
+      "ostatus": "http://ostatus.org#",
+      "atomUri": "ostatus:atomUri",
+      "inReplyToAtomUri": "ostatus:inReplyToAtomUri",
+      "conversation": "ostatus:conversation",
+      "sensitive": "as:sensitive",
+      "toot": "http://joinmastodon.org/ns#",
+      "votersCount": "toot:votersCount",
+      "fedibird": "http://fedibird.com/ns#",
+      "quoteUri": "fedibird:quoteUri",
+      "expiry": "fedibird:expiry"
+    }
+  ],
+  "id": "https://fedibird.com/users/noellabo/statuses/107712183700212249",
+  "type": "Note",
+  "summary": null,
+  "inReplyTo": null,
+  "published": "2022-01-30T15:44:50Z",
+  "url": "https://fedibird.com/@noellabo/107712183700212249",
+  "attributedTo": "https://fedibird.com/users/noellabo",
+  "to": [
+    "https://www.w3.org/ns/activitystreams#Public"
+  ],
+  "cc": [
+    "https://fedibird.com/users/noellabo/followers"
+  ],
+  "sensitive": false,
+  "atomUri": "https://fedibird.com/users/noellabo/statuses/107712183700212249",
+  "inReplyToAtomUri": null,
+  "conversation": "tag:fedibird.com,2022-01-30:objectId=107712183700170473:objectType=Conversation",
+  "context": "https://fedibird.com/contexts/107712183700170473",
+  "quoteUri": "https://unnerv.jp/users/UN_NERV/statuses/107712176849067434",
+  "_misskey_quote": "https://unnerv.jp/users/UN_NERV/statuses/107712176849067434",
+  "_misskey_content": "揺れていたようだ",
+  "content": "<p>揺れていたようだ<span class=\"quote-inline\"><br/>QT: <a class=\"status-url-link\" data-status-account-acct=\"UN_NERV@unnerv.jp\" data-status-id=\"107712177062934465\" href=\"https://unnerv.jp/@UN_NERV/107712176849067434\" rel=\"nofollow noopener noreferrer\" target=\"_blank\"><span class=\"invisible\">https://</span><span class=\"ellipsis\">unnerv.jp/@UN_NERV/10771217684</span><span class=\"invisible\">9067434</span></a></span></p>",
+  "contentMap": {
+    "ja": "<p>揺れていたようだ<span class=\"quote-inline\"><br/>QT: <a class=\"status-url-link\" data-status-account-acct=\"UN_NERV@unnerv.jp\" data-status-id=\"107712177062934465\" href=\"https://unnerv.jp/@UN_NERV/107712176849067434\" rel=\"nofollow noopener noreferrer\" target=\"_blank\"><span class=\"invisible\">https://</span><span class=\"ellipsis\">unnerv.jp/@UN_NERV/10771217684</span><span class=\"invisible\">9067434</span></a></span></p>"
+  },
+  "attachment": [],
+  "tag": [],
+  "replies": {
+    "id": "https://fedibird.com/users/noellabo/statuses/107712183700212249/replies",
+    "type": "Collection",
+    "first": {
+      "type": "CollectionPage",
+      "next": "https://fedibird.com/users/noellabo/statuses/107712183700212249/replies?only_other_accounts=true&page=true",
+      "partOf": "https://fedibird.com/users/noellabo/statuses/107712183700212249/replies",
+      "items": []
+    }
+  }
+}
diff --git a/test/fixtures/quote_post/fedibird_quote_post.json b/test/fixtures/quote_post/fedibird_quote_post.json
new file mode 100644
index 000000000..ebf383356
--- /dev/null
+++ b/test/fixtures/quote_post/fedibird_quote_post.json
@@ -0,0 +1,52 @@
+{
+  "@context": [
+    "https://www.w3.org/ns/activitystreams",
+    {
+      "ostatus": "http://ostatus.org#",
+      "atomUri": "ostatus:atomUri",
+      "inReplyToAtomUri": "ostatus:inReplyToAtomUri",
+      "conversation": "ostatus:conversation",
+      "sensitive": "as:sensitive",
+      "toot": "http://joinmastodon.org/ns#",
+      "votersCount": "toot:votersCount",
+      "expiry": "toot:expiry"
+    }
+  ],
+  "id": "https://fedibird.com/users/noellabo/statuses/107663670404015196",
+  "type": "Note",
+  "summary": null,
+  "inReplyTo": null,
+  "published": "2022-01-22T02:07:16Z",
+  "url": "https://fedibird.com/@noellabo/107663670404015196",
+  "attributedTo": "https://fedibird.com/users/noellabo",
+  "to": [
+    "https://www.w3.org/ns/activitystreams#Public"
+  ],
+  "cc": [
+    "https://fedibird.com/users/noellabo/followers"
+  ],
+  "sensitive": false,
+  "atomUri": "https://fedibird.com/users/noellabo/statuses/107663670404015196",
+  "inReplyToAtomUri": null,
+  "conversation": "tag:fedibird.com,2022-01-22:objectId=107663670404038002:objectType=Conversation",
+  "context": "https://fedibird.com/contexts/107663670404038002",
+  "quoteURL": "https://misskey.io/notes/8vsn2izjwh",
+  "_misskey_quote": "https://misskey.io/notes/8vsn2izjwh",
+  "_misskey_content": "いつの生まれだシトリン",
+  "content": "<p>いつの生まれだシトリン<span class=\"quote-inline\"><br/>QT: <a class=\"status-url-link\" data-status-account-acct=\"Citrine@misskey.io\" data-status-id=\"107663207194225003\" href=\"https://misskey.io/notes/8vsn2izjwh\" rel=\"nofollow noopener noreferrer\" target=\"_blank\"><span class=\"invisible\">https://</span><span class=\"\">misskey.io/notes/8vsn2izjwh</span><span class=\"invisible\"></span></a></span></p>",
+  "contentMap": {
+    "ja": "<p>いつの生まれだシトリン<span class=\"quote-inline\"><br/>QT: <a class=\"status-url-link\" data-status-account-acct=\"Citrine@misskey.io\" data-status-id=\"107663207194225003\" href=\"https://misskey.io/notes/8vsn2izjwh\" rel=\"nofollow noopener noreferrer\" target=\"_blank\"><span class=\"invisible\">https://</span><span class=\"\">misskey.io/notes/8vsn2izjwh</span><span class=\"invisible\"></span></a></span></p>"
+  },
+  "attachment": [],
+  "tag": [],
+  "replies": {
+    "id": "https://fedibird.com/users/noellabo/statuses/107663670404015196/replies",
+    "type": "Collection",
+    "first": {
+      "type": "CollectionPage",
+      "next": "https://fedibird.com/users/noellabo/statuses/107663670404015196/replies?only_other_accounts=true&page=true",
+      "partOf": "https://fedibird.com/users/noellabo/statuses/107663670404015196/replies",
+      "items": []
+    }
+  }
+}
diff --git a/test/fixtures/quote_post/fedibird_quote_uri.json b/test/fixtures/quote_post/fedibird_quote_uri.json
new file mode 100644
index 000000000..7c328fdb9
--- /dev/null
+++ b/test/fixtures/quote_post/fedibird_quote_uri.json
@@ -0,0 +1,54 @@
+{
+  "@context": [
+    "https://www.w3.org/ns/activitystreams",
+    {
+      "ostatus": "http://ostatus.org#",
+      "atomUri": "ostatus:atomUri",
+      "inReplyToAtomUri": "ostatus:inReplyToAtomUri",
+      "conversation": "ostatus:conversation",
+      "sensitive": "as:sensitive",
+      "toot": "http://joinmastodon.org/ns#",
+      "votersCount": "toot:votersCount",
+      "fedibird": "http://fedibird.com/ns#",
+      "quoteUri": "fedibird:quoteUri",
+      "expiry": "fedibird:expiry"
+    }
+  ],
+  "id": "https://fedibird.com/users/noellabo/statuses/107699335988346142",
+  "type": "Note",
+  "summary": null,
+  "inReplyTo": null,
+  "published": "2022-01-28T09:17:30Z",
+  "url": "https://fedibird.com/@noellabo/107699335988346142",
+  "attributedTo": "https://fedibird.com/users/noellabo",
+  "to": [
+    "https://www.w3.org/ns/activitystreams#Public"
+  ],
+  "cc": [
+    "https://fedibird.com/users/noellabo/followers"
+  ],
+  "sensitive": false,
+  "atomUri": "https://fedibird.com/users/noellabo/statuses/107699335988346142",
+  "inReplyToAtomUri": null,
+  "conversation": "tag:fedibird.com,2022-01-28:objectId=107699335988345290:objectType=Conversation",
+  "context": "https://fedibird.com/contexts/107699335988345290",
+  "quoteUri": "https://fedibird.com/users/yamako/statuses/107699333438289729",
+  "_misskey_quote": "https://fedibird.com/users/yamako/statuses/107699333438289729",
+  "_misskey_content": "美味しそう",
+  "content": "<p>美味しそう<span class=\"quote-inline\"><br/>QT: <a class=\"status-url-link\" data-status-account-acct=\"yamako\" data-status-id=\"107699333438289729\" href=\"https://fedibird.com/@yamako/107699333438289729\" rel=\"nofollow noopener noreferrer\" target=\"_blank\"><span class=\"invisible\">https://</span><span class=\"ellipsis\">fedibird.com/@yamako/107699333</span><span class=\"invisible\">438289729</span></a></span></p>",
+  "contentMap": {
+    "ja": "<p>美味しそう<span class=\"quote-inline\"><br/>QT: <a class=\"status-url-link\" data-status-account-acct=\"yamako\" data-status-id=\"107699333438289729\" href=\"https://fedibird.com/@yamako/107699333438289729\" rel=\"nofollow noopener noreferrer\" target=\"_blank\"><span class=\"invisible\">https://</span><span class=\"ellipsis\">fedibird.com/@yamako/107699333</span><span class=\"invisible\">438289729</span></a></span></p>"
+  },
+  "attachment": [],
+  "tag": [],
+  "replies": {
+    "id": "https://fedibird.com/users/noellabo/statuses/107699335988346142/replies",
+    "type": "Collection",
+    "first": {
+      "type": "CollectionPage",
+      "next": "https://fedibird.com/users/noellabo/statuses/107699335988346142/replies?only_other_accounts=true&page=true",
+      "partOf": "https://fedibird.com/users/noellabo/statuses/107699335988346142/replies",
+      "items": []
+    }
+  }
+}
diff --git a/test/fixtures/quote_post/fep-e232-tag-example.json b/test/fixtures/quote_post/fep-e232-tag-example.json
new file mode 100644
index 000000000..23c7fb5ac
--- /dev/null
+++ b/test/fixtures/quote_post/fep-e232-tag-example.json
@@ -0,0 +1,17 @@
+{
+  "@context": "https://www.w3.org/ns/activitystreams",
+  "type": "Note",
+  "content": "This is a quote:<br>RE: https://server.example/objects/123",
+  "tag": [
+    {
+      "type": "Link",
+      "mediaType": "application/ld+json; profile=\"https://www.w3.org/ns/activitystreams\"",
+      "href": "https://server.example/objects/123",
+      "name": "RE: https://server.example/objects/123"
+    }
+  ],
+  "id": "https://server.example/objects/1",
+  "to": "https://server.example/users/1",
+  "attributedTo": "https://server.example/users/1",
+  "actor": "https://server.example/users/1"
+}
diff --git a/test/fixtures/quote_post/misskey_quote_post.json b/test/fixtures/quote_post/misskey_quote_post.json
new file mode 100644
index 000000000..59f677ca9
--- /dev/null
+++ b/test/fixtures/quote_post/misskey_quote_post.json
@@ -0,0 +1,46 @@
+{
+  "@context": [
+    "https://www.w3.org/ns/activitystreams",
+    "https://w3id.org/security/v1",
+    {
+      "manuallyApprovesFollowers": "as:manuallyApprovesFollowers",
+      "sensitive": "as:sensitive",
+      "Hashtag": "as:Hashtag",
+      "quoteUrl": "as:quoteUrl",
+      "toot": "http://joinmastodon.org/ns#",
+      "Emoji": "toot:Emoji",
+      "featured": "toot:featured",
+      "discoverable": "toot:discoverable",
+      "schema": "http://schema.org#",
+      "PropertyValue": "schema:PropertyValue",
+      "value": "schema:value",
+      "misskey": "https://misskey.io/ns#",
+      "_misskey_content": "misskey:_misskey_content",
+      "_misskey_quote": "misskey:_misskey_quote",
+      "_misskey_reaction": "misskey:_misskey_reaction",
+      "_misskey_votes": "misskey:_misskey_votes",
+      "_misskey_talk": "misskey:_misskey_talk",
+      "isCat": "misskey:isCat",
+      "vcard": "http://www.w3.org/2006/vcard/ns#"
+    }
+  ],
+  "id": "https://misskey.io/notes/8vs6ylpfez",
+  "type": "Note",
+  "attributedTo": "https://misskey.io/users/7rkrarq81i",
+  "summary": null,
+  "content": "<p><span>投稿者の設定によるね<br>Fanboxについても投稿者によっては過去の投稿は高額なプランに移動してることがある<br><br>RE: </span><a href=\"https://misskey.io/notes/8vs6wxufd0\">https://misskey.io/notes/8vs6wxufd0</a></p>",
+  "_misskey_content": "投稿者の設定によるね\nFanboxについても投稿者によっては過去の投稿は高額なプランに移動してることがある",
+  "_misskey_quote": "https://misskey.io/notes/8vs6wxufd0",
+  "quoteUrl": "https://misskey.io/notes/8vs6wxufd0",
+  "published": "2022-01-21T16:38:30.243Z",
+  "to": [
+    "https://www.w3.org/ns/activitystreams#Public"
+  ],
+  "cc": [
+    "https://misskey.io/users/7rkrarq81i/followers"
+  ],
+  "inReplyTo": null,
+  "attachment": [],
+  "sensitive": false,
+  "tag": []
+}
diff --git a/test/fixtures/tesla_mock/aimu@misskey.io.json b/test/fixtures/tesla_mock/aimu@misskey.io.json
new file mode 100644
index 000000000..9ff4cb6d0
--- /dev/null
+++ b/test/fixtures/tesla_mock/aimu@misskey.io.json
@@ -0,0 +1,64 @@
+{
+  "@context": [
+    "https://www.w3.org/ns/activitystreams",
+    "https://w3id.org/security/v1",
+    {
+      "manuallyApprovesFollowers": "as:manuallyApprovesFollowers",
+      "sensitive": "as:sensitive",
+      "Hashtag": "as:Hashtag",
+      "quoteUrl": "as:quoteUrl",
+      "toot": "http://joinmastodon.org/ns#",
+      "Emoji": "toot:Emoji",
+      "featured": "toot:featured",
+      "discoverable": "toot:discoverable",
+      "schema": "http://schema.org#",
+      "PropertyValue": "schema:PropertyValue",
+      "value": "schema:value",
+      "misskey": "https://misskey.io/ns#",
+      "_misskey_content": "misskey:_misskey_content",
+      "_misskey_quote": "misskey:_misskey_quote",
+      "_misskey_reaction": "misskey:_misskey_reaction",
+      "_misskey_votes": "misskey:_misskey_votes",
+      "_misskey_talk": "misskey:_misskey_talk",
+      "isCat": "misskey:isCat",
+      "vcard": "http://www.w3.org/2006/vcard/ns#"
+    }
+  ],
+  "type": "Person",
+  "id": "https://misskey.io/users/83ssedkv53",
+  "inbox": "https://misskey.io/users/83ssedkv53/inbox",
+  "outbox": "https://misskey.io/users/83ssedkv53/outbox",
+  "followers": "https://misskey.io/users/83ssedkv53/followers",
+  "following": "https://misskey.io/users/83ssedkv53/following",
+  "sharedInbox": "https://misskey.io/inbox",
+  "endpoints": {
+    "sharedInbox": "https://misskey.io/inbox"
+  },
+  "url": "https://misskey.io/@aimu",
+  "preferredUsername": "aimu",
+  "name": "あいむ",
+  "summary": "<p><span>わずかな作曲要素 巣穴で独り言<br>Twitter </span><a href=\"https://twitter.com/aimu_53\">https://twitter.com/aimu_53</a><span><br>Soundcloud </span><a href=\"https://soundcloud.com/aimu-53\">https://soundcloud.com/aimu-53</a></p>",
+  "icon": {
+    "type": "Image",
+    "url": "https://s3.arkjp.net/misskey/webpublic-3f7e93c0-34f5-443c-acc0-f415cb2342b4.jpg",
+    "sensitive": false,
+    "name": null
+  },
+  "image": {
+    "type": "Image",
+    "url": "https://s3.arkjp.net/misskey/webpublic-2db63d1d-490b-488b-ab62-c93c285f26b6.png",
+    "sensitive": false,
+    "name": null
+  },
+  "tag": [],
+  "manuallyApprovesFollowers": false,
+  "discoverable": true,
+  "publicKey": {
+    "id": "https://misskey.io/users/83ssedkv53#main-key",
+    "type": "Key",
+    "owner": "https://misskey.io/users/83ssedkv53",
+    "publicKeyPem": "-----BEGIN PUBLIC KEY-----\nMIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEA1ylhePJ6qGHmwHSBP17b\nIosxGaiFKvgDBgZdm8vzvKeRSqJV9uLHfZL3pO/Zt02EwaZd2GohZAtBZEF8DbMA\n3s93WAesvyGF9mjGrYYKlhp/glwyrrrbf+RdD0DLtyDwRRlrxp3pS2lLmv5Tp1Zl\npH+UKpOnNrpQqjHI5P+lEc9bnflzbRrX+UiyLNsVAP80v4wt7SZfT/telrU6mDru\n998UdfhUo7bDKeDsHG1PfLpyhhtfdoZub4kBpkyacHiwAd+CdCjR54Eu7FDwVK3p\nY3JcrT2q5stgMqN1m4QgSL4XAADIotWwDYttTJejM1n9dr+6VWv5bs0F2Q/6gxOp\nu5DQZLk4Q+64U4LWNox6jCMOq3fYe0g7QalJIHnanYQQo+XjoH6S1Aw64gQ3Ip2Y\nZBmZREAOR7GMFVDPFnVnsbCHnIAv16TdgtLgQBAihkWEUuPqITLi8PMu6kMr3uyq\nYkObEfH0TNTcqaiVpoXv791GZLEUV5ROl0FSUANLNkHZZv29xZ5JDOBOR1rNBLyH\ngVtW8rpszYqOXwzX23hh4WsVXfB7YgNvIijwjiaWbzsecleaENGEnLNMiVKVumTj\nmtyTeFJpH0+OaSrUYpemRRJizmqIjklKsNwUEwUb2WcUUg92o56T2obrBkooabZe\nwgSXSKTOcjsR/ju7+AuIyvkCAwEAAQ==\n-----END PUBLIC KEY-----\n"
+  },
+  "isCat": true,
+  "vcard:bday": "5353-05-03"
+}
diff --git a/test/fixtures/tesla_mock/misskey.io_8vs6wxufd0.json b/test/fixtures/tesla_mock/misskey.io_8vs6wxufd0.json
new file mode 100644
index 000000000..323ca10ed
--- /dev/null
+++ b/test/fixtures/tesla_mock/misskey.io_8vs6wxufd0.json
@@ -0,0 +1,44 @@
+{
+  "@context": [
+    "https://www.w3.org/ns/activitystreams",
+    "https://w3id.org/security/v1",
+    {
+      "manuallyApprovesFollowers": "as:manuallyApprovesFollowers",
+      "sensitive": "as:sensitive",
+      "Hashtag": "as:Hashtag",
+      "quoteUrl": "as:quoteUrl",
+      "toot": "http://joinmastodon.org/ns#",
+      "Emoji": "toot:Emoji",
+      "featured": "toot:featured",
+      "discoverable": "toot:discoverable",
+      "schema": "http://schema.org#",
+      "PropertyValue": "schema:PropertyValue",
+      "value": "schema:value",
+      "misskey": "https://misskey.io/ns#",
+      "_misskey_content": "misskey:_misskey_content",
+      "_misskey_quote": "misskey:_misskey_quote",
+      "_misskey_reaction": "misskey:_misskey_reaction",
+      "_misskey_votes": "misskey:_misskey_votes",
+      "_misskey_talk": "misskey:_misskey_talk",
+      "isCat": "misskey:isCat",
+      "vcard": "http://www.w3.org/2006/vcard/ns#"
+    }
+  ],
+  "id": "https://misskey.io/notes/8vs6wxufd0",
+  "type": "Note",
+  "attributedTo": "https://misskey.io/users/83ssedkv53",
+  "summary": null,
+  "content": "<p><span>Fantiaこれできないように過去のやつは従量課金だった気がする</span></p>",
+  "_misskey_content": "Fantiaこれできないように過去のやつは従量課金だった気がする",
+  "published": "2022-01-21T16:37:12.663Z",
+  "to": [
+    "https://www.w3.org/ns/activitystreams#Public"
+  ],
+  "cc": [
+    "https://misskey.io/users/83ssedkv53/followers"
+  ],
+  "inReplyTo": null,
+  "attachment": [],
+  "sensitive": false,
+  "tag": []
+}
diff --git a/test/pleroma/web/activity_pub/builder_test.exs b/test/pleroma/web/activity_pub/builder_test.exs
index eb175a1be..52058a0a3 100644
--- a/test/pleroma/web/activity_pub/builder_test.exs
+++ b/test/pleroma/web/activity_pub/builder_test.exs
@@ -44,5 +44,34 @@ defmodule Pleroma.Web.ActivityPub.BuilderTest do
 
       assert {:ok, ^expected, []} = Builder.note(draft)
     end
+
+    test "quote post" do
+      user = insert(:user)
+      note = insert(:note)
+
+      draft = %ActivityDraft{
+        user: user,
+        context: "2hu",
+        content_html: "<h1>This is :moominmamma: note</h1>",
+        quote_post: note,
+        extra: %{}
+      }
+
+      expected = %{
+        "actor" => user.ap_id,
+        "attachment" => [],
+        "content" => "<h1>This is :moominmamma: note</h1>",
+        "context" => "2hu",
+        "sensitive" => false,
+        "type" => "Note",
+        "quoteUrl" => note.data["id"],
+        "cc" => [],
+        "summary" => nil,
+        "tag" => [],
+        "to" => []
+      }
+
+      assert {:ok, ^expected, []} = Builder.note(draft)
+    end
   end
 end
diff --git a/test/pleroma/web/activity_pub/mrf/inline_quote_policy_test.exs b/test/pleroma/web/activity_pub/mrf/inline_quote_policy_test.exs
new file mode 100644
index 000000000..d5762766f
--- /dev/null
+++ b/test/pleroma/web/activity_pub/mrf/inline_quote_policy_test.exs
@@ -0,0 +1,112 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Web.ActivityPub.MRF.InlineQuotePolicyTest do
+  alias Pleroma.Web.ActivityPub.MRF.InlineQuotePolicy
+  use Pleroma.DataCase
+
+  test "adds quote URL to post content" do
+    quote_url = "https://gleasonator.com/objects/1234"
+
+    activity = %{
+      "type" => "Create",
+      "actor" => "https://gleasonator.com/users/alex",
+      "object" => %{
+        "type" => "Note",
+        "content" => "Nice post",
+        "quoteUrl" => quote_url
+      }
+    }
+
+    {:ok, %{"object" => %{"content" => filtered}}} = InlineQuotePolicy.filter(activity)
+
+    assert filtered ==
+             "Nice post<span class=\"quote-inline\"><br/><br/><bdi>RT:</bdi> <a href=\"https://gleasonator.com/objects/1234\">https://gleasonator.com/objects/1234</a></span>"
+  end
+
+  test "adds quote URL to post content, custom template" do
+    clear_config([:mrf_inline_quote, :template], "{url}'s quoting")
+    quote_url = "https://gleasonator.com/objects/1234"
+
+    activity = %{
+      "type" => "Create",
+      "actor" => "https://gleasonator.com/users/alex",
+      "object" => %{
+        "type" => "Note",
+        "content" => "Nice post",
+        "quoteUrl" => quote_url
+      }
+    }
+
+    {:ok, %{"object" => %{"content" => filtered}}} = InlineQuotePolicy.filter(activity)
+
+    assert filtered ==
+             "Nice post<span class=\"quote-inline\"><br/><br/><a href=\"https://gleasonator.com/objects/1234\">https://gleasonator.com/objects/1234</a>'s quoting</span>"
+  end
+
+  test "doesn't add line breaks to markdown posts" do
+    quote_url = "https://gleasonator.com/objects/1234"
+
+    activity = %{
+      "type" => "Create",
+      "actor" => "https://gleasonator.com/users/alex",
+      "object" => %{
+        "type" => "Note",
+        "content" => "<p>Nice post</p>",
+        "quoteUrl" => quote_url
+      }
+    }
+
+    {:ok, %{"object" => %{"content" => filtered}}} = InlineQuotePolicy.filter(activity)
+
+    assert filtered ==
+             "<p>Nice post<span class=\"quote-inline\"><br/><br/><bdi>RT:</bdi> <a href=\"https://gleasonator.com/objects/1234\">https://gleasonator.com/objects/1234</a></span></p>"
+  end
+
+  test "ignores Misskey quote posts" do
+    object = File.read!("test/fixtures/quote_post/misskey_quote_post.json") |> Jason.decode!()
+
+    activity = %{
+      "type" => "Create",
+      "actor" => "https://misskey.io/users/7rkrarq81i",
+      "object" => object
+    }
+
+    {:ok, filtered} = InlineQuotePolicy.filter(activity)
+    assert filtered == activity
+  end
+
+  test "ignores Fedibird quote posts" do
+    object = File.read!("test/fixtures/quote_post/fedibird_quote_post.json") |> Jason.decode!()
+
+    # Normally the ObjectValidator will fix this before it reaches MRF
+    object = Map.put(object, "quoteUrl", object["quoteURL"])
+
+    activity = %{
+      "type" => "Create",
+      "actor" => "https://fedibird.com/users/noellabo",
+      "object" => object
+    }
+
+    {:ok, filtered} = InlineQuotePolicy.filter(activity)
+    assert filtered == activity
+  end
+
+  test "skips objects which already have an .inline-quote span" do
+    object =
+      File.read!("test/fixtures/quote_post/fedibird_quote_mismatched.json") |> Jason.decode!()
+
+    # Normally the ObjectValidator will fix this before it reaches MRF
+    object = Map.put(object, "quoteUrl", object["quoteUri"])
+
+    activity = %{
+      "type" => "Create",
+      "actor" => "https://fedibird.com/users/noellabo",
+      "object" => object
+    }
+
+    {:ok, filtered} = InlineQuotePolicy.filter(activity)
+    assert filtered == activity
+  end
+end
diff --git a/test/pleroma/web/activity_pub/mrf/quote_to_link_tag_policy_test.exs b/test/pleroma/web/activity_pub/mrf/quote_to_link_tag_policy_test.exs
new file mode 100644
index 000000000..96b49b6a0
--- /dev/null
+++ b/test/pleroma/web/activity_pub/mrf/quote_to_link_tag_policy_test.exs
@@ -0,0 +1,73 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2023 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Web.ActivityPub.MRF.QuoteToLinkTagPolicyTest do
+  alias Pleroma.Web.ActivityPub.MRF.QuoteToLinkTagPolicy
+
+  use Pleroma.DataCase
+
+  require Pleroma.Constants
+
+  test "Add quote url to Link tag" do
+    quote_url = "https://gleasonator.com/objects/1234"
+
+    activity = %{
+      "type" => "Create",
+      "actor" => "https://gleasonator.com/users/alex",
+      "object" => %{
+        "type" => "Note",
+        "content" => "Nice post",
+        "quoteUrl" => quote_url
+      }
+    }
+
+    {:ok, %{"object" => object}} = QuoteToLinkTagPolicy.filter(activity)
+
+    assert object["tag"] == [
+             %{
+               "type" => "Link",
+               "href" => quote_url,
+               "mediaType" => Pleroma.Constants.activity_json_canonical_mime_type()
+             }
+           ]
+  end
+
+  test "Add quote url to Link tag, append to the end" do
+    quote_url = "https://gleasonator.com/objects/1234"
+
+    activity = %{
+      "type" => "Create",
+      "actor" => "https://gleasonator.com/users/alex",
+      "object" => %{
+        "type" => "Note",
+        "content" => "Nice post",
+        "quoteUrl" => quote_url,
+        "tag" => [%{"type" => "Hashtag", "name" => "#foo"}]
+      }
+    }
+
+    {:ok, %{"object" => object}} = QuoteToLinkTagPolicy.filter(activity)
+
+    assert [_, tag] = object["tag"]
+
+    assert tag == %{
+             "type" => "Link",
+             "href" => quote_url,
+             "mediaType" => Pleroma.Constants.activity_json_canonical_mime_type()
+           }
+  end
+
+  test "Bypass posts without quoteUrl" do
+    activity = %{
+      "type" => "Create",
+      "actor" => "https://gleasonator.com/users/alex",
+      "object" => %{
+        "type" => "Note",
+        "content" => "Nice post"
+      }
+    }
+
+    assert {:ok, ^activity} = QuoteToLinkTagPolicy.filter(activity)
+  end
+end
diff --git a/test/pleroma/web/activity_pub/object_validators/article_note_page_validator_test.exs b/test/pleroma/web/activity_pub/object_validators/article_note_page_validator_test.exs
index c7a62be18..4703c3801 100644
--- a/test/pleroma/web/activity_pub/object_validators/article_note_page_validator_test.exs
+++ b/test/pleroma/web/activity_pub/object_validators/article_note_page_validator_test.exs
@@ -116,4 +116,53 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.ArticleNotePageValidatorTest
 
     %{valid?: true} = ArticleNotePageValidator.cast_and_validate(note)
   end
+
+  test "Fedibird quote post" do
+    insert(:user, ap_id: "https://fedibird.com/users/noellabo")
+
+    data = File.read!("test/fixtures/quote_post/fedibird_quote_post.json") |> Jason.decode!()
+    cng = ArticleNotePageValidator.cast_and_validate(data)
+
+    assert cng.valid?
+    assert cng.changes.quoteUrl == "https://misskey.io/notes/8vsn2izjwh"
+  end
+
+  test "Fedibird quote post with quoteUri field" do
+    insert(:user, ap_id: "https://fedibird.com/users/noellabo")
+
+    data = File.read!("test/fixtures/quote_post/fedibird_quote_uri.json") |> Jason.decode!()
+    cng = ArticleNotePageValidator.cast_and_validate(data)
+
+    assert cng.valid?
+    assert cng.changes.quoteUrl == "https://fedibird.com/users/yamako/statuses/107699333438289729"
+  end
+
+  test "Misskey quote post" do
+    insert(:user, ap_id: "https://misskey.io/users/7rkrarq81i")
+
+    data = File.read!("test/fixtures/quote_post/misskey_quote_post.json") |> Jason.decode!()
+    cng = ArticleNotePageValidator.cast_and_validate(data)
+
+    assert cng.valid?
+    assert cng.changes.quoteUrl == "https://misskey.io/notes/8vs6wxufd0"
+  end
+
+  test "Parse tag as quote" do
+    # https://codeberg.org/fediverse/fep/src/branch/main/fep/e232/fep-e232.md
+
+    insert(:user, ap_id: "https://server.example/users/1")
+
+    data = File.read!("test/fixtures/quote_post/fep-e232-tag-example.json") |> Jason.decode!()
+    cng = ArticleNotePageValidator.cast_and_validate(data)
+
+    assert cng.valid?
+    assert cng.changes.quoteUrl == "https://server.example/objects/123"
+
+    assert Enum.at(cng.changes.tag, 0).changes == %{
+             type: "Link",
+             mediaType: "application/ld+json; profile=\"https://www.w3.org/ns/activitystreams\"",
+             href: "https://server.example/objects/123",
+             name: "RE: https://server.example/objects/123"
+           }
+  end
 end
diff --git a/test/pleroma/web/activity_pub/transmogrifier_test.exs b/test/pleroma/web/activity_pub/transmogrifier_test.exs
index 3e0c8dc65..5e58d75db 100644
--- a/test/pleroma/web/activity_pub/transmogrifier_test.exs
+++ b/test/pleroma/web/activity_pub/transmogrifier_test.exs
@@ -123,7 +123,7 @@ defmodule Pleroma.Web.ActivityPub.TransmogrifierTest do
       assert activity.data["context"] == object.data["context"]
     end
 
-    test "it drops link tags" do
+    test "it keeps link tags" do
       insert(:user, ap_id: "https://example.org/users/alice")
 
       message = File.read!("test/fixtures/fep-e232.json") |> Jason.decode!()
@@ -131,10 +131,29 @@ defmodule Pleroma.Web.ActivityPub.TransmogrifierTest do
       assert {:ok, activity} = Transmogrifier.handle_incoming(message)
 
       object = Object.normalize(activity)
-      assert length(object.data["tag"]) == 1
+      assert [%{"type" => "Mention"}, %{"type" => "Link"}] = object.data["tag"]
+    end
+
+    test "it accepts quote posts" do
+      insert(:user, ap_id: "https://misskey.io/users/7rkrarq81i")
+
+      object = File.read!("test/fixtures/quote_post/misskey_quote_post.json") |> Jason.decode!()
+
+      message = %{
+        "@context" => "https://www.w3.org/ns/activitystreams",
+        "type" => "Create",
+        "actor" => "https://misskey.io/users/7rkrarq81i",
+        "object" => object
+      }
+
+      assert {:ok, activity} = Transmogrifier.handle_incoming(message)
 
-      tag = object.data["tag"] |> List.first()
-      assert tag["type"] == "Mention"
+      # Object was created in the database
+      object = Object.normalize(activity)
+      assert object.data["quoteUrl"] == "https://misskey.io/notes/8vs6wxufd0"
+
+      # It fetched the quoted post
+      assert Object.normalize("https://misskey.io/notes/8vs6wxufd0")
     end
   end
 
@@ -350,6 +369,20 @@ defmodule Pleroma.Web.ActivityPub.TransmogrifierTest do
                }
              } = prepared["object"]
     end
+
+    test "it prepares a quote post" do
+      user = insert(:user)
+
+      {:ok, quoted_post} = CommonAPI.post(user, %{status: "hey"})
+      {:ok, quote_post} = CommonAPI.post(user, %{status: "hey", quote_id: quoted_post.id})
+
+      {:ok, modified} = Transmogrifier.prepare_outgoing(quote_post.data)
+
+      %{data: %{"id" => quote_id}} = Object.normalize(quoted_post)
+
+      assert modified["object"]["quoteUrl"] == quote_id
+      assert modified["object"]["quoteUri"] == quote_id
+    end
   end
 
   describe "actor rewriting" do
diff --git a/test/pleroma/web/common_api/activity_draft_test.exs b/test/pleroma/web/common_api/activity_draft_test.exs
new file mode 100644
index 000000000..02bc6cf3b
--- /dev/null
+++ b/test/pleroma/web/common_api/activity_draft_test.exs
@@ -0,0 +1,33 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.Web.CommonAPI.ActivityDraftTest do
+  use Pleroma.DataCase
+
+  alias Pleroma.Web.CommonAPI
+  alias Pleroma.Web.CommonAPI.ActivityDraft
+
+  import Pleroma.Factory
+
+  test "create/2 with a quote post" do
+    user = insert(:user)
+    another_user = insert(:user)
+
+    {:ok, direct} = CommonAPI.post(user, %{status: ".", visibility: "direct"})
+    {:ok, private} = CommonAPI.post(user, %{status: ".", visibility: "private"})
+    {:ok, unlisted} = CommonAPI.post(user, %{status: ".", visibility: "unlisted"})
+    {:ok, local} = CommonAPI.post(user, %{status: ".", visibility: "local"})
+    {:ok, public} = CommonAPI.post(user, %{status: ".", visibility: "public"})
+
+    {:error, _} = ActivityDraft.create(user, %{status: "nice", quote_id: direct.id})
+    {:ok, _} = ActivityDraft.create(user, %{status: "nice", quote_id: private.id})
+    {:error, _} = ActivityDraft.create(another_user, %{status: "nice", quote_id: private.id})
+    {:ok, _} = ActivityDraft.create(user, %{status: "nice", quote_id: unlisted.id})
+    {:ok, _} = ActivityDraft.create(another_user, %{status: "nice", quote_id: unlisted.id})
+    {:ok, _} = ActivityDraft.create(user, %{status: "nice", quote_id: local.id})
+    {:ok, _} = ActivityDraft.create(another_user, %{status: "nice", quote_id: local.id})
+    {:ok, _} = ActivityDraft.create(user, %{status: "nice", quote_id: public.id})
+    {:ok, _} = ActivityDraft.create(another_user, %{status: "nice", quote_id: public.id})
+  end
+end
diff --git a/test/pleroma/web/common_api_test.exs b/test/pleroma/web/common_api_test.exs
index 0d76d6581..a98b16d4b 100644
--- a/test/pleroma/web/common_api_test.exs
+++ b/test/pleroma/web/common_api_test.exs
@@ -796,6 +796,53 @@ defmodule Pleroma.Web.CommonAPITest do
         scheduled_at: expires_at
       )
     end
+
+    test "it allows quote posting" do
+      user = insert(:user)
+
+      {:ok, quoted} = CommonAPI.post(user, %{status: "Hello world"})
+      {:ok, quote_post} = CommonAPI.post(user, %{status: "nice post", quote_id: quoted.id})
+
+      quoted = Object.normalize(quoted)
+      quote_post = Object.normalize(quote_post)
+
+      assert quote_post.data["quoteUrl"] == quoted.data["id"]
+
+      # The OP is not mentioned
+      refute quoted.data["actor"] in quote_post.data["to"]
+    end
+
+    test "quote posting with explicit addressing doesn't mention the OP" do
+      user = insert(:user)
+
+      {:ok, quoted} = CommonAPI.post(user, %{status: "Hello world"})
+
+      {:ok, quote_post} =
+        CommonAPI.post(user, %{status: "nice post", quote_id: quoted.id, to: []})
+
+      assert Object.normalize(quote_post).data["to"] == [Pleroma.Constants.as_public()]
+    end
+
+    test "quote posting visibility" do
+      user = insert(:user)
+      another_user = insert(:user)
+
+      {:ok, direct} = CommonAPI.post(user, %{status: ".", visibility: "direct"})
+      {:ok, private} = CommonAPI.post(user, %{status: ".", visibility: "private"})
+      {:ok, unlisted} = CommonAPI.post(user, %{status: ".", visibility: "unlisted"})
+      {:ok, local} = CommonAPI.post(user, %{status: ".", visibility: "local"})
+      {:ok, public} = CommonAPI.post(user, %{status: ".", visibility: "public"})
+
+      {:error, _} = CommonAPI.post(user, %{status: "nice", quote_id: direct.id})
+      {:ok, _} = CommonAPI.post(user, %{status: "nice", quote_id: private.id})
+      {:error, _} = CommonAPI.post(another_user, %{status: "nice", quote_id: private.id})
+      {:ok, _} = CommonAPI.post(user, %{status: "nice", quote_id: unlisted.id})
+      {:ok, _} = CommonAPI.post(another_user, %{status: "nice", quote_id: unlisted.id})
+      {:ok, _} = CommonAPI.post(user, %{status: "nice", quote_id: local.id})
+      {:ok, _} = CommonAPI.post(another_user, %{status: "nice", quote_id: local.id})
+      {:ok, _} = CommonAPI.post(user, %{status: "nice", quote_id: public.id})
+      {:ok, _} = CommonAPI.post(another_user, %{status: "nice", quote_id: public.id})
+    end
   end
 
   describe "reactions" do
diff --git a/test/pleroma/web/mastodon_api/controllers/status_controller_test.exs b/test/pleroma/web/mastodon_api/controllers/status_controller_test.exs
index 76c289ee7..de3b52e26 100644
--- a/test/pleroma/web/mastodon_api/controllers/status_controller_test.exs
+++ b/test/pleroma/web/mastodon_api/controllers/status_controller_test.exs
@@ -125,6 +125,28 @@ defmodule Pleroma.Web.MastodonAPI.StatusControllerTest do
       )
     end
 
+    test "posting a quote post", %{conn: conn} do
+      user = insert(:user)
+
+      {:ok, %{id: activity_id} = activity} = CommonAPI.post(user, %{status: "yolo"})
+      %{data: %{"id" => quote_url}} = Object.normalize(activity)
+
+      conn =
+        conn
+        |> put_req_header("content-type", "application/json")
+        |> post("/api/v1/statuses", %{
+          "status" => "indeed",
+          "quote_id" => activity_id
+        })
+
+      assert %{
+               "id" => id,
+               "pleroma" => %{"quote" => %{"id" => ^activity_id}, "quote_url" => ^quote_url}
+             } = json_response_and_validate_schema(conn, 200)
+
+      assert Activity.get_by_id(id)
+    end
+
     test "it fails to create a status if `expires_in` is less or equal than an hour", %{
       conn: conn
     } do
diff --git a/test/pleroma/web/mastodon_api/views/status_view_test.exs b/test/pleroma/web/mastodon_api/views/status_view_test.exs
index b93335190..baa9b32f5 100644
--- a/test/pleroma/web/mastodon_api/views/status_view_test.exs
+++ b/test/pleroma/web/mastodon_api/views/status_view_test.exs
@@ -326,6 +326,10 @@ defmodule Pleroma.Web.MastodonAPI.StatusViewTest do
         conversation_id: convo_id,
         context: object_data["context"],
         in_reply_to_account_acct: nil,
+        quote: nil,
+        quote_id: nil,
+        quote_url: nil,
+        quote_visible: false,
         content: %{"text/plain" => HTML.strip_tags(object_data["content"])},
         spoiler_text: %{"text/plain" => HTML.strip_tags(object_data["summary"])},
         expires_at: nil,
@@ -422,6 +426,88 @@ defmodule Pleroma.Web.MastodonAPI.StatusViewTest do
     assert status.in_reply_to_id == to_string(note.id)
   end
 
+  test "a quote post" do
+    post = insert(:note_activity)
+    user = insert(:user)
+
+    {:ok, quote_post} = CommonAPI.post(user, %{status: "he", quote_id: post.id})
+    {:ok, quoted_quote_post} = CommonAPI.post(user, %{status: "yo", quote_id: quote_post.id})
+
+    status = StatusView.render("show.json", %{activity: quoted_quote_post})
+
+    assert status.pleroma.quote.id == to_string(quote_post.id)
+    assert status.pleroma.quote_id == to_string(quote_post.id)
+    assert status.pleroma.quote_url == Object.normalize(quote_post).data["id"]
+    assert status.pleroma.quote_visible
+
+    # Quotes don't go more than one level deep
+    refute status.pleroma.quote.pleroma.quote
+    assert status.pleroma.quote.pleroma.quote_id == to_string(post.id)
+    assert status.pleroma.quote.pleroma.quote_url == Object.normalize(post).data["id"]
+    assert status.pleroma.quote.pleroma.quote_visible
+
+    # In an index
+    [status] = StatusView.render("index.json", %{activities: [quoted_quote_post], as: :activity})
+
+    assert status.pleroma.quote.id == to_string(quote_post.id)
+  end
+
+  test "quoted private post" do
+    user = insert(:user)
+
+    # Insert a private post
+    private = insert(:followers_only_note_activity, user: user)
+    private_object = Object.normalize(private)
+
+    # Create a public post quoting the private post
+    quote_private =
+      insert(:note_activity, note: insert(:note, data: %{"quoteUrl" => private_object.data["id"]}))
+
+    status = StatusView.render("show.json", %{activity: quote_private})
+
+    # The quote isn't rendered
+    refute status.pleroma.quote
+    assert status.pleroma.quote_url == private_object.data["id"]
+    refute status.pleroma.quote_visible
+
+    # After following the user, the quote is rendered
+    follower = insert(:user)
+    CommonAPI.follow(follower, user)
+
+    status = StatusView.render("show.json", %{activity: quote_private, for: follower})
+    assert status.pleroma.quote.id == to_string(private.id)
+    assert status.pleroma.quote_visible
+  end
+
+  test "quoted direct message" do
+    # Insert a direct message
+    direct = insert(:direct_note_activity)
+    direct_object = Object.normalize(direct)
+
+    # Create a public post quoting the direct message
+    quote_direct =
+      insert(:note_activity, note: insert(:note, data: %{"quoteUrl" => direct_object.data["id"]}))
+
+    status = StatusView.render("show.json", %{activity: quote_direct})
+
+    # The quote isn't rendered
+    refute status.pleroma.quote
+    assert status.pleroma.quote_url == direct_object.data["id"]
+    refute status.pleroma.quote_visible
+  end
+
+  test "repost of quote post" do
+    post = insert(:note_activity)
+    user = insert(:user)
+
+    {:ok, quote_post} = CommonAPI.post(user, %{status: "he", quote_id: post.id})
+    {:ok, repost} = CommonAPI.repeat(quote_post.id, user)
+
+    [status] = StatusView.render("index.json", %{activities: [repost], as: :activity})
+
+    assert status.reblog.pleroma.quote.id == to_string(post.id)
+  end
+
   test "contains mentions" do
     user = insert(:user)
     mentioned = insert(:user)
diff --git a/test/support/http_request_mock.ex b/test/support/http_request_mock.ex
index b0cf613ac..78a367024 100644
--- a/test/support/http_request_mock.ex
+++ b/test/support/http_request_mock.ex
@@ -1380,6 +1380,15 @@ defmodule HttpRequestMock do
      }}
   end
 
+  def get("https://misskey.io/users/83ssedkv53", _, _, _) do
+    {:ok,
+     %Tesla.Env{
+       status: 200,
+       body: File.read!("test/fixtures/tesla_mock/aimu@misskey.io.json"),
+       headers: activitypub_object_headers()
+     }}
+  end
+
   def get("https://gleasonator.com/users/macgirvin", _, _, _) do
     {:ok,
      %Tesla.Env{
@@ -1446,6 +1455,15 @@ defmodule HttpRequestMock do
      }}
   end
 
+  def get("https://misskey.io/notes/8vs6wxufd0", _, _, _) do
+    {:ok,
+     %Tesla.Env{
+       status: 200,
+       body: File.read!("test/fixtures/tesla_mock/misskey.io_8vs6wxufd0.json"),
+       headers: activitypub_object_headers()
+     }}
+  end
+
   def get(url, query, body, headers) do
     {:error,
      "Mock response not implemented for GET #{inspect(url)}, #{query}, #{inspect(body)}, #{inspect(headers)}"}