images overlapping until browser resize

Hi, like the plugin but encountering one issue…

Problem:
– thumbnails overlap until I resize the browser window, then the masonry effect kicks in.

Couple points:
– I am using the latest plugin.
– website is fully responsive with fixed max-width.
– media thumbnails height is set 9999px (to allow for variables).
– media thumbnails width is set 250px.
– page renders a ‘ghost placeholder’ thumbnail of 250×250 when thumbnail has a height less than 250px.
– when thumbnail has a height greater than 250px it is displayed fully but overlaps the image direct below it.
– ALL overlapping/’ghost placeholder’ issues disappear when browser is resized and thumbnails display CORRECTLY in a masonry view.

What is causing the thumbnail issue not to render correctly on page load?

Thanks.

https://ww.wp.xz.cn/plugins/jquery-masonry-image-gallery/