WordPress at a glance
filter is not described

the_editor_content filter-hook . WP 2.1.0

Filters the default editor content.

Usage

add_filter( 'the_editor_content', 'filter_function_name_3580', 10, 2 );
function filter_function_name_3580( $content, $default_editor ){
	// filter...

	return $content;
}
$content(string)
Default editor content.
$default_editor(string)
The default editor for the current user. Either 'html' or 'tinymce'.

Where the hook is called

_WP_Editors::editor()
WP_Widget_Text::form()
wp-includes/class-wp-editor.php 273
$content = apply_filters( 'the_editor_content', $content, $default_editor );
wp-includes/widgets/class-wp-widget-text.php 456
$text = apply_filters( 'the_editor_content', $instance['text'], $default_editor );

Where the hook is used (in WP core)

wp-includes/class-wp-editor.php 261
add_filter( 'the_editor_content', 'format_for_editor', 10, 2 );
wp-includes/class-wp-editor.php 277
remove_filter( 'the_editor_content', 'format_for_editor' );
wp-includes/widgets/class-wp-widget-text.php 449
add_filter( 'the_editor_content', 'format_for_editor', 10, 2 );
wp-includes/widgets/class-wp-widget-text.php 460
remove_filter( 'the_editor_content', 'format_for_editor' );