Hi,
I have been using YT Shortcodes for a while including the YouTube video shortcode.
This seemed to work fine when I first installed it but I noticed that the web page size seemed to double for no reason.
I have replaced the YouTube YT Shortcode with the AllVideos plugin and the web page has reverted to it's normal size.
See the GTMetrix report summaries for details:
Attachment please-explain.jpg not found
I have lost confidence in YT Shortcodes and won't be using it in the meantime.
Hopefully there is a reasonable explanation.