dzoltak

Hi,

I contacted AWS support and they were able to reproduce the problem.

Here is the reason why:

I have been able to successfully reproduce the issue with a WordPress site running on an EC2 instance sitting behind an ELB and accessible through a CloudFront distribution.
I have also found the reasoning behind this. The answer lies with the modification of the User-Agent HTTP header that goes through CloudFront. CloudFront essentially modifies the User-Agent header to: Amazon CloudFront.
The visual WYSIWYG editor is only made available based on the User-Agent header and since WordPress does not anticipate the User-Agent to be ‘Amazon CloudFront’, WordPress disables the visual editor.
The exact function that accomplishes this is located in wordpress/wp-includes/general-template.php file:
function user_can_richedit() {
global $wp_rich_edit, $is_gecko, $is_opera, $is_safari, $is_chrome, $is_IE;

if ( !isset($wp_rich_edit) ) {
$wp_rich_edit = false;

if ( get_user_option( ‘rich_editing’ ) == ‘true’ || ! is_user_logged_in() ) { // default to ‘true’ for logged out users
if ( $is_safari ) {
$wp_rich_edit = ! wp_is_mobile() || ( preg_match( ‘!AppleWebKit/(\d+)!’, $_SERVER[‘HTTP_USER_AGENT’], $match ) && intval( $match[1] ) >= 534 );
} elseif ( $is_gecko || $is_chrome || $is_IE || ( $is_opera && !wp_is_mobile() ) ) {
$wp_rich_edit = true;
}
}
}
/**
* Filter whether the user can access the rich (Visual) editor.
*
* @since 2.1.0
*
* @param bool $wp_rich_edit Whether the user can access to the rich (Visual) editor.
*/
return apply_filters( ‘user_can_richedit’, $wp_rich_edit );
}

Once I modified the function above to have the wp_rich_edit variable to always evaluate to true, I was able to see the Visual Editor just fine through CloudFront. However, I would suggest that you modify the above code to anticipate that the $_SERVER[‘HTTP_USER_AGENT’] could be ‘Amazon CloudFront’ and then test the functionality of WordPress editor.

WordPress needs to be updated to support CloudFront as a user-agent or there needs to be a way to force it to always use the Visual Editor.