WordPress Master-Master Replication Conflicts Caused by Gutenberg Blocks

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Our company uses a WordPress setup with two servers behind a load balancer, and we rely on master-master MySQL replication. To prevent replication conflicts, cron jobs are configured to run only on a single server. This setup has worked seamlessly for several years, but we started encountering weekly replication conflicts around two months ago.

The conflict occurs with the following SQL queries:

### DELETE FROM `fr_wp`.`wp_sitemeta`
### WHERE
###   @1=385338
###   @2=1
###   @3='_site_transient_wp_theme_files_patterns-39b075616449d092b365a81b6f9d3e6d'
###   @4='a:2:{s:7:"version";s:0:"";s:8:"patterns";a:0:{}}'

### DELETE FROM `fr_wp`.`wp_sitemeta`
### WHERE
###   @1=385336
###   @2=1
###   @3='_site_transient_timeout_wp_theme_files_patterns-39b075616449d092b365a81b6f9d3e6d'
###   @4='1737837003'
# at 150934730

Upon reviewing the WordPress source code, I identified that these conflicts are caused by the WordPress function _register_theme_block_patterns being executed at the exact same time on both servers.

Since our site does not use Gutenberg blocks, we resolved the issue by preventing this function from being executed:

<?php
remove_action('init', '_register_theme_block_patterns');