After Update to v3.0 I can’t enter in wp-admin over https

Somehow I think this update is buggy and this error has the same origins as this https://www.ads-software.com/support/topic/website-broken-with-3-0/#post-8189007 . Have you tried checking your server logs (if you have access)

Same issue here on one of our sites

After update to 3.0.2 problem still exist

Hi,

Yeah 3.0 contained a bug which caused the headers generated by HTTP2/Server Push to exceed the limits on nginx and fastcgi. This resulted in customers seeing 520 or 502 http error codes when loading their site. This has been fixed in 3.0.2 because we removed the HTTP2/Server Push functionality.

Thanks,
John