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Adding images to blog posts should be super easy right!? RIGHT.
Now, if you're PRO and thus have Asset Uploading as a feature, you'll see an Asset Uploader right in the Post Editor:
Like everywhere else you can upload Assets, you can drag and drop them into the dotted area. The new Asset will upload and drop in, where you can click it to get the URL.
Here's a GIF of the whole flow:
I know I've been wanting this ever since writing my first post with an image in it.
Note that the Asset Uploader widget is very limited in functionality. It's all about making new uploads easy. You can't delete assets from there (although you can overwrite same-named Assets). For full-featured access to your assets, we have the Asset Manager.