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A support email from Sten Hougaard brought to our attention that our Export as Gist feature leads to a lot of Gists with not very useful names.
We've changed that up so that we now include a Markdown file as well that contains the name of the Pen, its description, and the license. Now when you export a Gist, the Gist itself is a lot more readable at a glance.
Because we make the Markdown file "first" in the list, it is used as the name and preview. It will be easier to find what you are looking for in the list of Gists that is part of your GitHub profile.
For moving code from a Gist back to CodePen, the CodePen Bookmarklet is a good way to do that.
Some of you have requested that we update the Gist if you have already exported it before, rather than create a new one. If any of you have feelings one way or another about that, we'd love to hear. Remember you can export as .zip as well. Here's our full documentation on exporting.