Root and Sub Directory Execution Problem

My core WordPress files are in a sub directory. When the site is run from there, everything works as designed. When I change the option – for WordPress home – to the root of my site, the block editor won’t save changes or publish and eventually present the JSON error. The classic editor works.

To run from the root (with a sub dir install), I add the subdir to the require statement in the index file at the root of the site.

/** Loads the WordPress Environment and Template */
require( dirname( __FILE__ ) . '/subdir/wp-blog-header.php' );

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