diff --git a/priv/repo/migrations/20200722185515_fix_malformed_formatter_config.exs b/priv/repo/migrations/20200722185515_fix_malformed_formatter_config.exs
new file mode 100644
index 000000000..77b760825
--- /dev/null
+++ b/priv/repo/migrations/20200722185515_fix_malformed_formatter_config.exs
@@ -0,0 +1,26 @@
+defmodule Pleroma.Repo.Migrations.FixMalformedFormatterConfig do
+  use Ecto.Migration
+  alias Pleroma.ConfigDB
+
+  @config_path %{group: :pleroma, key: Pleroma.Formatter}
+
+  def change do
+    with %ConfigDB{value: %{} = opts} <- ConfigDB.get_by_params(@config_path),
+         fixed_opts <- Map.to_list(opts) do
+      fix_config(fixed_opts)
+    else
+      _ -> :skipped
+    end
+  end
+
+  defp fix_config(fixed_opts) when is_list(fixed_opts) do
+    {:ok, _} =
+      ConfigDB.update_or_create(%{
+        group: :pleroma,
+        key: Pleroma.Formatter,
+        value: fixed_opts
+      })
+
+    :ok
+  end
+end
diff --git a/test/migrations/20200722185515_fix_malformed_formatter_config_test.exs b/test/migrations/20200722185515_fix_malformed_formatter_config_test.exs
new file mode 100644
index 000000000..9e8f997a0
--- /dev/null
+++ b/test/migrations/20200722185515_fix_malformed_formatter_config_test.exs
@@ -0,0 +1,62 @@
+defmodule Pleroma.Repo.Migrations.FixMalformedFormatterConfigTest do
+  use Pleroma.DataCase
+  import Pleroma.Factory
+  import Pleroma.Tests.Helpers, only: [require_migration: 1]
+  alias Pleroma.ConfigDB
+
+  setup_all do: require_migration("20200722185515_fix_malformed_formatter_config")
+
+  test "change/0 converts a map into a list", %{migration: migration} do
+    incorrect_opts = %{
+      class: false,
+      extra: true,
+      new_window: false,
+      rel: "ugc",
+      strip_prefix: false
+    }
+
+    insert(:config, group: :pleroma, key: Pleroma.Formatter, value: incorrect_opts)
+
+    assert :ok == migration.change()
+
+    %{value: new_opts} = ConfigDB.get_by_params(%{group: :pleroma, key: Pleroma.Formatter})
+
+    assert new_opts == [
+             class: false,
+             extra: true,
+             new_window: false,
+             rel: "ugc",
+             strip_prefix: false
+           ]
+
+    {text, _mentions, []} =
+      Pleroma.Formatter.linkify(
+        "https://www.businessinsider.com/walmart-will-close-stores-on-thanksgiving-ending-black-friday-tradition-2020-7\n\nOmg will COVID finally end Black Friday???"
+      )
+
+    assert text ==
+             "<a href=\"https://www.businessinsider.com/walmart-will-close-stores-on-thanksgiving-ending-black-friday-tradition-2020-7\" rel=\"ugc\">https://www.businessinsider.com/walmart-will-close-stores-on-thanksgiving-ending-black-friday-tradition-2020-7</a>\n\nOmg will COVID finally end Black Friday???"
+  end
+
+  test "change/0 skips if Pleroma.Formatter config is already a list", %{migration: migration} do
+    opts = [
+      class: false,
+      extra: true,
+      new_window: false,
+      rel: "ugc",
+      strip_prefix: false
+    ]
+
+    insert(:config, group: :pleroma, key: Pleroma.Formatter, value: opts)
+
+    assert :skipped == migration.change()
+
+    %{value: new_opts} = ConfigDB.get_by_params(%{group: :pleroma, key: Pleroma.Formatter})
+
+    assert new_opts == opts
+  end
+
+  test "change/0 skips if Pleroma.Formatter is empty", %{migration: migration} do
+    assert :skipped == migration.change()
+  end
+end