I hadn't run into the undo problem before. I'm going to look into that one and see if we can fix that - that sounds like a very unpleasant failure mode. I'm sorry you ran into it.
I keep a pretty close eye on our failure rates. When our browser editor hits an error, it sends back a distress signal. (Of course, the nightmare for me would be when the error is so bad that it can't even send a distress signal - but I don't think that is happening much). We had some higher error rates in the end of September and early October, did some fixes, and got them back down again. We keep working on getting it even lower.
We have better cloning/copying/organizing/sourcecontrol on the road map. We may do an out-of-browser IDE, too, but we haven't settled on what that would look like.
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