[Plugin: WordPress Related Posts] thumbnails to big on iPad

Great plugin but…

Today i noticed that the thumbnails in the sidebar and below the post on a iPad are scaled to big. On a desktop PC and smartphone they are also to big when loading but they shrink during loading. After that they are the right size.

I allready cleared my cache files and tried different browsers and different iPad.

What could be the problem over here?

https://www.ads-software.com/extend/plugins/wordpress-23-related-posts-plugin/