Can’t Publish Events in Gutenberg Mode

I found that if I have Gutenberg mode and try to update an event with recurrences it fails with the following error message:

This event has validation errors and cannot be published until they are fixed: Main recurrence set times are required.

I was able to workaround this problem with the following code snippet:

/**
 * Intercept and bypass Events Manager Gutenberg API validation errors
 * without breaking the classic meta-box layout bindings.
 */
add_action( 'wp_enqueue_scripts', 'wp_override_em_gutenberg_validation_response', 999 ); // Front-end if needed
add_action( 'admin_enqueue_scripts', 'wp_override_em_gutenberg_validation_response', 999 ); // Backend editor

function wp_override_em_gutenberg_validation_response() {
    // Only run this inside the WordPress Admin area on post editing screens
    if ( ! is_admin() ) {
        return;
    }

    // Intercept the global fetch mechanism used by apiFetch in Gutenberg
    // to force any response from the EM validation endpoint to return true.
    $override_js = "
        (function() {
            if ( window.wp && window.wp.apiFetch ) {
                const originalApiFetch = window.wp.apiFetch;
                window.wp.apiFetch = function( options ) {
                    // Check if apiFetch is hitting the Events Manager validation endpoint
                    if ( options && options.path && options.path.includes('em/validation') ) {
                        return originalApiFetch( options ).then( function( response ) {
                            // If the server rejected the snapshot, force it to valid anyway
                            if ( response && response.valid === false ) {
                                console.warn('[EM Patch] Bypassing REST validation error for Gutenberg updates.');
                                response.valid = true;
                                response.errors = [];
                            }
                            return response;
                        });
                    }
                    return originalApiFetch( options );
                };
            }
        })();
    ";

    // Inject our script inline so it executes before/alongside the validation file
    wp_add_inline_script( 'wp-api-fetch', $override_js, 'after' );
}

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