Scratch

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You should be able to export projects in compatibility to earlier versions of Scratch.

For instance with 1.3.1 to 1.2.1.

If your project in 1.3.1 doesn't have anything that 1.2.1 has, (eg: lists, etc.) you should be able to save it for and open it in Scratch 1.2.1.

That way, if your friend has a REALLY SLOW internet connection, but has downloaded an old version of Scratch, you can send them a file from a newer version with only features that their version has, and they'll be able to open and use it.
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