Eliminate the Action->Loader waterfall

[colinclerk]

I was watching the Remix Single on Forms and I noticed a sequential waterfall in the Network after the form was submitted:

The GET doesn't run until after the POST completes. This makes sense, since it avoids a race condition where the GET retrieves data before the POST has had a chance to finalize the mutation.

But, I still wonder if this GET can be eliminated.

Instead of triggering the loader refresh from the client, can it be triggered on the server and added to the POST's response? This would eliminate the extra round trip.