Add callback for custom TinyMCE editor stylesheets.

The parameter $stylesheet is the name of the stylesheet, relative to the theme root. It also accepts an array of stylesheets. It is optional and defaults to ‘editor-style.css’.

This function automatically adds another stylesheet with -rtl prefix, e.g. editor-style-rtl.css. If that file doesn’t exist, it is removed before adding the stylesheet(s) to TinyMCE. If an array of stylesheets is passed to add_editor_style(), RTL is only added for the first stylesheet.

Since version 3.4 the TinyMCE body has .rtl CSS class. It is a better option to use that class and add any RTL styles to the main stylesheet.

Signature

add_editor_style( $stylesheet = 'editor-style.css' )
stylesheet
 (mixed) Optional. Stylesheet name or array thereof, relative to theme root. Defaults to 'editor-style.css'
Default: 'editor-style.css'

Return

(void)

Source

function add_editor_style( $stylesheet = 'editor-style.css' ) {

	add_theme_support( 'editor-style' );

	if ( ! is_admin() )
		return;

	global $editor_styles;
	$editor_styles = (array) $editor_styles;
	$stylesheet    = (array) $stylesheet;
	if ( is_rtl() ) {
		$rtl_stylesheet = str_replace('.css', '-rtl.css', $stylesheet[0]);
		$stylesheet[] = $rtl_stylesheet;
	}

	$editor_styles = array_merge( $editor_styles, $stylesheet );
}
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