wp-includes/theme.php:2229Retrieves any registered editor stylesheet URLs.
string[]One hook fires while get_editor_stylesheets() runs, in this order:
Filters the array of URLs of stylesheets applied to the editor.
function get_editor_stylesheets() { $stylesheets = array(); // Load editor_style.css if the active theme supports it. if ( ! empty( $GLOBALS['editor_styles'] ) && is_array( $GLOBALS['editor_styles'] ) ) { $editor_styles = $GLOBALS['editor_styles']; $editor_styles = array_unique( array_filter( $editor_styles ) ); $style_uri = get_stylesheet_directory_uri(); $style_dir = get_stylesheet_directory(); // Support externally referenced styles (like, say, fonts). foreach ( $editor_styles as $key => $file ) { if ( preg_match( '~^(https?:)?//~', $file ) ) { $stylesheets[] = sanitize_url( $file ); unset( $editor_styles[ $key ] ); } } // Look in a parent theme first, that way child theme CSS overrides. if ( is_child_theme() ) { $template_uri = get_template_directory_uri(); $template_dir = get_template_directory(); foreach ( $editor_styles as $key => $file ) { if ( $file && file_exists( "$template_dir/$file" ) ) { $stylesheets[] = "$template_uri/$file"; } } } foreach ( $editor_styles as $file ) { if ( $file && file_exists( "$style_dir/$file" ) ) { $stylesheets[] = "$style_uri/$file"; } } } /** * Filters the array of URLs of stylesheets applied to the editor. * * @since 4.3.0 * * @param string[] $stylesheets Array of URLs of stylesheets to be applied to the editor. */ return apply_filters( 'editor_stylesheets', $stylesheets );}Introduced in 4.0.0. Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/theme.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.