Allow using useBlocker without setting a beforeunload listener

[duniul]

Currently, useBlocker will always add a beforeunload event listener, which triggers a blocking alert box when leaving the page or closing the tab. However, there are situations where you might want to block internal navigation but don't want to block unload.

This would align it with react-router's behavior, which recommends users to set their own beforeunload listener instead.

Maybe just a prop like this could make sense to make it backwards compatible?

const blocker = useBlocker({ blockBeforeUnload: false })

Looking at the source code it would need to pass the option to the history's block method, which currently only accepts functions, but I don't know if that also needs to remain backwards compatible. In that case maybe it could be added as a second argument?

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Edit: Seems like #1790 might solve this issue, adding disableBeforeUnload as an option 👍