Customize Color Not Working

Can you try disabling your other plugins one by one to see if one of them is causing an error?

Same problem. I've removed the Code for remove query strings from the functions.php and everything works fine again.
This is the code i removed:

add_filter( 'style_loader_src', 'generate_remove_cssjs_ver', 10, 2 );
add_filter( 'script_loader_src', 'generate_remove_cssjs_ver', 10, 2 );
function generate_remove_cssjs_ver( $src ) {
	if( strpos( $src, '?ver=' ) )
		$src = remove_query_arg( 'ver', $src );
	
	return $src;
}

Removing query strings can cause all kinds of problems, although I haven't seen it cause this one before. Maybe try clearing your browser cache completely.

Hi Tom

I've removed all custom CSS and deactivated plugins, all working, then switched it all back on and everything is working again?

Thank you

Nigel

Must have been a caching issue :)