Features from optional dependencies

web-sys implicit feature

Enables web-sys

web-sys:

Bindings for all Web APIs, a procedurally generated crate from WebIDL

Affects htmlify::Htmlify.as_element, htmlify::append_to_document_body

yew implicit feature

Enables yew

yew:

A framework for creating reliable and efficient web applications

Affects htmlify::yew, htmlify::Htmlify.as_yew_node