What happened to Bonjour in Safari 11 and how do I access it?

In their wisdom, Apple have removed it without providing a direct workaround. In the meantime, you can use something like Bonjour Browser, which is less convenient but will at least get you to the right URLs for admin UIs etc.

Apple clearly removed that item from the Safari menu.

My take on this is everyone is wondering about Safari 11 and Bonjour. There is a suggestion that Apple needs to be reminded that it is huge to have Bonjour in Safari to manage printers, access scanners, even see some HomeKit device tech interfaces.

Everyone trusted Apple on Bonjour... and Safari is the preeminent end user tool to use and be introduced to the benefits of Bonjour...

consider posting your opinion on Safari-sans-Bonjour at:

Bonjour Feedback: https://www.apple.com/feedback/bonjour.html