Rename <Suspense unstable_expectedLoadTime> to <Suspense defer> and implement in SSR #35022
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This allows it to stream in and potentially animate.
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This is similar to what we do with prerenders.
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…mplement in SSR (#35022) We've long had the CPU suspense feature behind a flag under the terrible API `unstable_expectedLoadTime={arbitraryNumber}`. We've known for a long time we want it to just be `defer={true}` (or just `<Suspense defer>` in the short hand syntax). So this adds the new name and warns for the old name. For only the new name, I also implemented SSR semantics in Fizz. It has two effects here. 1) It renders the fallback before the content (similar to prerender) allowing siblings to complete quicker. 2) It always outlines the result. When streaming this should really happen naturally but if you defer a prerendered content it also implies that it's expensive and should be outlined. It gives you a opt-in to outlining similar to suspensey images and css but let you control it manually. DiffTrain build for [0ba2f01](0ba2f01)
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…mplement in SSR (#35022) We've long had the CPU suspense feature behind a flag under the terrible API `unstable_expectedLoadTime={arbitraryNumber}`. We've known for a long time we want it to just be `defer={true}` (or just `<Suspense defer>` in the short hand syntax). So this adds the new name and warns for the old name. For only the new name, I also implemented SSR semantics in Fizz. It has two effects here. 1) It renders the fallback before the content (similar to prerender) allowing siblings to complete quicker. 2) It always outlines the result. When streaming this should really happen naturally but if you defer a prerendered content it also implies that it's expensive and should be outlined. It gives you a opt-in to outlining similar to suspensey images and css but let you control it manually. DiffTrain build for [0ba2f01](0ba2f01)
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Follow up to #35022. It's now replaced by the `defer` option. Sounds like nobody is actually using this option, including Meta, so we can just delete it.
This was referenced Nov 6, 2025
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We've long had the CPU suspense feature behind a flag under the terrible API
unstable_expectedLoadTime={arbitraryNumber}. We've known for a long time we want it to just bedefer={true}(or just<Suspense defer>in the short hand syntax). So this adds the new name and warns for the old name.For only the new name, I also implemented SSR semantics in Fizz. It has two effects here.