We'll create fresh WordPress site with Disable Automatic Theme & Plugin Updates installed. You have 20 minutes to test the plugin after that site we'll be deleted.
At the core of this plugin, it is simply using the build in filters to disable automatic theme and plugin updates.
add_filter( 'plugins_auto_update_enabled', '__return_false' );
add_filter( 'themes_auto_update_enabled', '__return_false' );
If you are interested in contributing to this plugin, all issues should be addressed on Github. Pull requests welcome.