This happens to most of WordPress blogs when you sign in to your website’s Admin (wp-admin) page & whenever you try to navigate to different page or open a new page this error get displayed every time you do it.
Error: Safari can’t open page – because the server unexpectedly dropped the connection. This sometimes occurs when the server is busy. Wait for a few minutes, and then try again.
Here is how to fix this,
On Safari Menu bar > Preferences > Privacy > Remove all website data
On prompt select ‘Remove Now’
All cookies will be cleaned up & now test your website is working or not.
It should start working as normal.
Hope it helps,
Thanks & Regards