There will also be a migrate plugin, which we can use to emit deprecation warnings. That'll help "prove" our hypothesis in the wild (for a few weeks at least) even in the optimistic case where we think we might not need the migrate plugin for long.

In T356897#9525286, @Krinkle wrote:

There will also be a migrate plugin, which we can use to emit deprecation warnings. That'll help "prove" our hypothesis in the wild (for a few weeks at least) even in the optimistic case where we think we might not need the migrate plugin for long.

Excellent. Yes, let's try to not ship in migrate mode for multiple years again. :-)

FYI, jQuery 4.0.0 has been released today: https://blog.jquery.com/2026/01/17/jquery-4-0-0/.