Previously this had to be emsdk install sdk-releases-upstream-HASH The only thing preventing using just the hash was that there was no default for the backend, so defaulting to upstream fixes this. And then we can do emsdk install HASH
Previously this had to be emsdk install sdk-releases-upstream-HASH The only thing preventing using just the hash was that there was no default for the backend, so defaulting to upstream fixes this. And then we can do emsdk install HASH