Page load issue

Hi Frank,
Thank you for a great plugin, it is awesome!
I’m using it on all my sites, but have a small problem I’d like to raise and maybe you can direct me (I’m not asking you to solve it for me …)
In the following sites – http://www.spectoos.com and http://www.loopindex.com
When the pages start to load, the page freeze with a bad styling and after a second or two all components get to their styled position.
What is the problem and where should I start looking?

Thanks,
Guy.

https://ww.wp.xz.cn/plugins/autoptimize/