Because some projects act differently online than offline, I think it would be nice to be able to "preview" your project online before others can see it. Sharing would be a 2 step process. First, you would share it on scratch and it would go to a page online that only the author of the project could see. Then, if the author likes the way it turns out, they could press another button to completely share. If not, they could fix the problem and try again.
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You can do this easily by putting the project code in the notepad. This will make a page where it will act like it is online. To see what i am talking bout go here.
http://scratch.mit.edu/forums/viewtopic.php?pid=763#p763
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