It was discussed before that one of the features we're discussing here ("lossless resizing by dragging corner") was and is present in web version of Evernote on Firefox, because FF has that inbuilt in edit forms. You're using Webkit rendering for desktop client, which doesn't support that natively. A similar issue was present in WordPress (resizing worked in FF, but not in Webkit browsers). I just wanted to add that since WP 3.9 lossless resizing by dragging corners is also supported in Webkit browsers. I don't know how they've implemented it (maybe it's just TinyMCE 4 feature), but it as you can see certainly doable and you could take some inspiration and idea how to implement it from WP if you need some.