Rich Media Parser: Do not return just a title if nothing else is there.

lib/pleroma/web/rich_media/parsers/meta_tags_parser.ex

@@ -34,13 +34,15 @@ defmodule Pleroma.Web.RichMedia.Parsers.MetaTagsParser do
 
   defp maybe_put_title(%{title: _} = meta, _), do: meta
 
-  defp maybe_put_title(meta, html) do
+  defp maybe_put_title(meta, html) when meta != %{} do
     case get_page_title(html) do
       "" -> meta
       title -> Map.put_new(meta, :title, title)
     end
   end
 
+  defp maybe_put_title(meta, _), do: meta
+
   defp get_page_title(html) do
     Floki.find(html, "title") |> Floki.text()
   end

test/web/rich_media/parser_test.exs

@@ -9,6 +9,12 @@ defmodule Pleroma.Web.RichMedia.ParserTest do
       } ->
         %Tesla.Env{status: 200, body: File.read!("test/fixtures/rich_media/ogp.html")}
 
+      %{
+        method: :get,
+        url: "http://example.com/non-ogp"
+      } ->
+        %Tesla.Env{status: 200, body: File.read!("test/fixtures/rich_media/non_ogp_embed.html")}
+
       %{
         method: :get,
         url: "http://example.com/ogp-missing-title"
@@ -47,6 +53,11 @@ defmodule Pleroma.Web.RichMedia.ParserTest do
     assert {:error, _} = Pleroma.Web.RichMedia.Parser.parse("http://example.com/empty")
   end
 
+  test "doesn't just add a title" do
+    assert Pleroma.Web.RichMedia.Parser.parse("http://example.com/non-ogp") ==
+             {:error, "Found metadata was invalid or incomplete: %{}"}
+  end
+
   test "parses ogp" do
     assert Pleroma.Web.RichMedia.Parser.parse("http://example.com/ogp") ==
              {:ok,