4 files changed, 20 insertions, 11 deletions
diff --git a/lib/pleroma/helpers/uri_helper.ex b/lib/pleroma/helpers/uri_helper.ex
index 6d205a636..9c9e53447 100644
--- a/lib/pleroma/helpers/uri_helper.ex
+++ b/lib/pleroma/helpers/uri_helper.ex
@@ -15,6 +15,7 @@ defmodule Pleroma.Helpers.UriHelper do
     uri
     |> Map.put(:query, URI.encode_query(updated_params))
     |> URI.to_string()
+    |> String.replace_suffix("?", "")
   end
 
   def maybe_add_base("/" <> uri, base), do: Path.join([base, uri])
diff --git a/lib/pleroma/web/mastodon_api/views/account_view.ex b/lib/pleroma/web/mastodon_api/views/account_view.ex
index 7eb4e86fe..a811f81c2 100644
--- a/lib/pleroma/web/mastodon_api/views/account_view.ex
+++ b/lib/pleroma/web/mastodon_api/views/account_view.ex
@@ -182,9 +182,9 @@ defmodule Pleroma.Web.MastodonAPI.AccountView do
     display_name = user.name || user.nickname
 
     avatar = User.avatar_url(user) |> MediaProxy.url()
-    avatar_static = User.avatar_url(user) |> MediaProxy.preview_url()
+    avatar_static = User.avatar_url(user) |> MediaProxy.preview_url(output_format: "jpeg")
     header = User.banner_url(user) |> MediaProxy.url()
-    header_static = User.banner_url(user) |> MediaProxy.preview_url()
+    header_static = User.banner_url(user) |> MediaProxy.preview_url(output_format: "jpeg")
 
     following_count =
       if !user.hide_follows_count or !user.hide_follows or opts[:for] == user do
diff --git a/lib/pleroma/web/media_proxy/media_proxy.ex b/lib/pleroma/web/media_proxy/media_proxy.ex
index 6695d49ce..4cbe1cf89 100644
--- a/lib/pleroma/web/media_proxy/media_proxy.ex
+++ b/lib/pleroma/web/media_proxy/media_proxy.ex
@@ -4,6 +4,7 @@
 
 defmodule Pleroma.Web.MediaProxy do
   alias Pleroma.Config
+  alias Pleroma.Helpers.UriHelper
   alias Pleroma.Upload
   alias Pleroma.Web
   alias Pleroma.Web.MediaProxy.Invalidation
@@ -58,9 +59,9 @@ defmodule Pleroma.Web.MediaProxy do
 
   # Note: routing all URLs to preview handler (even local and whitelisted).
   #   Preview handler will call url/1 on decoded URLs, and applicable ones will detour media proxy.
-  def preview_url(url) do
+  def preview_url(url, preview_params \\ []) do
     if preview_enabled?() do
-      encode_preview_url(url)
+      encode_preview_url(url, preview_params)
     else
       url
     end
@@ -116,10 +117,10 @@ defmodule Pleroma.Web.MediaProxy do
     build_url(sig64, base64, filename(url))
   end
 
-  def encode_preview_url(url) do
+  def encode_preview_url(url, preview_params \\ []) do
     {base64, sig64} = base64_sig64(url)
 
-    build_preview_url(sig64, base64, filename(url))
+    build_preview_url(sig64, base64, filename(url), preview_params)
   end
 
   def decode_url(sig, url) do
@@ -155,8 +156,10 @@ defmodule Pleroma.Web.MediaProxy do
     proxy_url("proxy", sig_base64, url_base64, filename)
   end
 
-  def build_preview_url(sig_base64, url_base64, filename \\ nil) do
-    proxy_url("proxy/preview", sig_base64, url_base64, filename)
+  def build_preview_url(sig_base64, url_base64, filename \\ nil, preview_params \\ []) do
+    uri = proxy_url("proxy/preview", sig_base64, url_base64, filename)
+
+    UriHelper.append_uri_params(uri, preview_params)
   end
 
   def verify_request_path_and_url(
diff --git a/lib/pleroma/web/media_proxy/media_proxy_controller.ex b/lib/pleroma/web/media_proxy/media_proxy_controller.ex
index b1f00fa0c..33daa1e05 100644
--- a/lib/pleroma/web/media_proxy/media_proxy_controller.ex
+++ b/lib/pleroma/web/media_proxy/media_proxy_controller.ex
@@ -64,9 +64,14 @@ defmodule Pleroma.Web.MediaProxy.MediaProxyController do
     end
   end
 
-  # TODO: find a workaround so avatar_static and header_static can work.
-  # Those only permit GIFs for animation, so we have to permit a way to
-  # allow those to get real static variants.
+  defp handle_preview(
+         "image/" <> _ = _content_type,
+         %{params: %{"output_format" => "jpeg"}} = conn,
+         url
+       ) do
+    handle_jpeg_preview(conn, url)
+  end
+
   defp handle_preview("image/gif" = _content_type, conn, url) do
     mediaproxy_url = url |> MediaProxy.url()