Summary:

To prepare for automatic effect dependencies, some codebases may want to
codemod
existing useEffect calls with no deps to include an explicit undefined
second argument
in order to preserve the "run on every render" behavior. In sufficiently
large codebases,
this may require a temporary enforcement period where all effects
provide an explicit
dependencies argument.

Outside of migration, relying on a component to render can lead to real
bugs,
especially when working with memoization.

There seems to be some bugs still to work out in Chrome. See #33187.

Additionally, since you can't really rely on this function existing
across browsers, it's hard to depend on its behavior anyway. In fact,
you now have a source of inconsistent behaviors across browsers to deal
with.

Ideally it would also be more widely spread in fake DOM implementations
like JSDOM so that we can use it unconditionally. #33177.

We still want to enable this since it's a great feature but maybe not
until it's more widely available cross-browsers with fewer bugs.

This is the same technique we do for the client except we don't check
whether this is newly created font loading to keep code small.

Unfortunately, we can't use this technique for Suspensey images. They'll
need to block before we call `startViewTransition` in a separate
refactor. This is due to a bug in Chrome where `img.decode()` doesn't
resolve until `startViewTransition` does.