Logging changes of settings in Customizer

[lukecarbis]

Resolves #308.

Thanks @marcin-lawrowski for finding this. I've tested it and it works well.

@westonruter Would you mind reviewing this one-liner? Any unintended side-effects?

[westonruter]

Using the customize_save action is a good way to capture whether the setting updates are being made in the Customizer, yes: https://github.com/xwp/wordpress-develop/blob/deaabdcc28bfbdc78d90040ece81250563b84779/src/wp-includes/class-wp-customize-manager.php#L999-L1020

The PHPDoc will need to be updated from:

Trigger this connector from WP CLI, only for known Settings

[lukecarbis]

Good catch. Thanks @westonruter.