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function is not described

_preview_theme_template_filter() WP 2.9.0

Deprecated from version 4.3.0. It is no longer supported and can be removed in future releases. It is recommended to replace this function with the same one.

Private function to modify the current template when previewing a theme

This is an internal function for using it by WP core itself. It's not recommended to use this function in your code.

No Hooks.

Return

String. Null. Nothing.

Usage

_preview_theme_template_filter();

Changelog

Since 2.9.0 Introduced.
Deprecated 4.3.0

Code of _preview_theme_template_filter() WP 5.7.1

<?php
function _preview_theme_template_filter() {
	_deprecated_function( __FUNCTION__, '4.3.0' );
	return '';
}