error loading spinner.gif with custom folder structure

Hi there,

have been loving your plugin ever since it’s release! I just noticed a small (non-breaking) bug: if you have a custom folder structure on your wordpress install, where your wp-content folder is outside the core folder, the “spinner.gif” won’t be loaded, since the location of the plugin’s css file is somewhere else relative to the wp-content folder.

The only fix that comes to my mind would be to use php to detetct the location of /wp-admin/images/ dynamically. As a temporary fix I put this into our functions.php file:

add_action( 'admin_footer', 'b09_spo_css_override' );

function b09_spo_css_override() {
	$images_url = site_url() . '/wp-admin/images/';
	?>
	<style>
		.spo-updating-row .check-column {
			background-image: url('<?php echo $images_url ?>spinner.gif') !important;
		}
		@media print,
		(-o-min-device-pixel-ratio: 5/4),
		(-webkit-min-device-pixel-ratio: 1.25),
		(min-resolution: 120dpi) {
			.spo-updating-row .check-column {
				background-image: url('<?php echo $images_url ?>spinner-2x.gif') !important;
				background-size: 20px 20px;
			}
		}
	</style>
	<?php
}

https://ww.wp.xz.cn/plugins/simple-page-ordering/