diff --git a/todo.txt b/todo.txt
index 897024b0f7..fc027a0c8b 100644
--- a/todo.txt
+++ b/todo.txt
@@ -39,3 +39,5 @@
 - Implement cloud saves by downloading the savegame from the web browser.
 
 - Find some developer with a MacBook and $100 to publish the 'OpenTTD Webapp Launcher' to the Apple Store.
+
+- Fast forward button requires separate rendering thread, implement frameskip instead.