do_action( 'customize_save', WP_Customize_Manager $manager )
Fires once the theme has switched in the Customizer, but before settings have been saved.
Parameters
- $manager
-  (WP_Customize_Manager) WP_Customize_Manager instance. 
Source
Changelog
| Version | Description | 
|---|---|
| 3.4.0 | Introduced. | 
    © 2003–2021 WordPress Foundation
Licensed under the GNU GPLv2+ License.
    https://developer.wordpress.org/reference/hooks/customize_save