Add "Bot" to User Agent to coerce Twitter into serving OGP <meta> tags.

CHANGELOG.md

@@ -76,6 +76,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Resolving Peertube accounts with Webfinger
 - `blob:` urls not being allowed by connect-src CSP
 - Mastodon API: fix `GET /api/v1/notifications` not returning the full result set
+- Rich Media Previews for Twitter links
 
 ## [Unreleased (patch)]
 

lib/pleroma/web/rich_media/parser.ex

@@ -86,7 +86,10 @@ defp parse_url(url) do
       end
 
     try do
-      {:ok, %Tesla.Env{body: html}} = Pleroma.HTTP.get(url, [], adapter: opts)
+      rich_media_agent = Pleroma.Application.user_agent() <> "; Bot"
+
+      {:ok, %Tesla.Env{body: html}} =
+        Pleroma.HTTP.get(url, [{"user-agent", rich_media_agent}], adapter: opts)
 
       html
       |> parse_html()