Hello Duncan,

Thanks for submitting this Idea however when a user creates an Event or clones an Activity this information does appear on the Project Timeline:

The screenshot above shows me (the "Admin User") creating an Activity ("00106: Staff - Other - Leave") and an Event ("12: Event on Project Timeline").

I've marked this Idea as "Already exists" but let me know if I have misunderstood your request?

Thanks,

Luke