That's important of course, but the cached code will have to be refreshed when there's a change (could be done partially with code splitting), so how long the c

That's important of course, but the cached code will have to be refreshed when there's a change (could be done partially with code splitting), so how long the cached data lasts depends on how often the Search page is updated. For Google that probably isn't happening daily, but it could be very often. Hopefully Google have split out the hot code that changes a lot in to a small bundle so the rest can sit in the cache for a while.