Hi Stephan,
you do not need a turbo frame to submit a form. Just use a normal form with id like:
<form action="/activities/new"
method="POST"
id="b__activity_edit">
<!-- form content -->
</form>
Then just return a Turbo stream with id of the form and action replace like:
<turbo-stream action="replace" target="b__activity_edit">
<template>
<h1>Update</h1>
</template>
</turbo-stream>
I use that in my side project Baralga, a web based time tracker GitHub - Baralga/backend: Baralga Server Backend for multi-user capable time tracking.
Bye,
Jan