Hey @Maro 
It’s a current limitation of the Supabase plugin in WeWeb because we do an automatic SELECT after an INSERT. The tech team is aware and will look to improve this.
In the meantime, you can use our REST API plugin to make your INSERT call to Supabase. If you’re not sure where to find the API endpoints to make the call in Supabase, here’s a video to another user that might help.
If you get stuck, don’t hesitate to create a new topic with a short video or some screenshots showing us how things are setup on the Supabase and WeWeb side of things. We’ll do our best to help out 