Right now I do this (https://wordpress.stackexchange.com/a/228763/114486) so as to add in WordPress 5.8.1
This work to half when I attempt to choose new template from dropdown.
It will not settle for apart from bodily information so I caught. Is there one thing that I lacking from updates of WP?
Why not different logic? I take advantage of WP with REST API as a headless content material. I added relaxation endpoint to get template as a logic to make use of correct template file on frontend. Use It as a model of frontend to decide on and customized fields might be align to correctly present web page up