I’m now seeing reports from some users about this, others are able to package just fine. I’m investigating this issue right now. @ has a workaround for people who compiled the engine from source code, but I’m looking to find a real fix first. Seems to only occur in the most recent 4.8 builds, not earlier 4.8 preview builds. As soon as I know something, I’ll let you know.
I’ve updated the first post with this warning.
Actually about to start streaming, if you want to watch progress on this issue.