after installation above the head of site I see:
Strict Standards: Non-static method YtFrameworkTemplate::ieversion() should not be called statically, assuming $this from incompatible context inC:\OpenServer\domains\g2.loc\plugins\system\yt\includes\libs\yt-minify.php on line 305

It repeates several times. How to delete it?

Dear sir,

You should go to your admin >> Global Configuration >> Server tab >> try to set 'Simple' in 'Error Reporting'

Thanks