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It's now easier than ever to upload an avatar for your CodePen account.
If you want to change it, now you have a bunch of options. You can grab your avatar from Twitter or GitHub in one click (if you aren't authorized, that'll just take another click). You can also pick any photo you are tagged in from Facebook. You can also still drag-and-drop or select a new image from your computer.
Here's a super quick video demonstrating them all: