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Credits+link for stb_textedit.h
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 Embeds [proggy_clean](http://upperbounds.net) font by Tristan Grimmer (MIT license).
 Embeds [M+ fonts](http://mplus-fonts.sourceforge.jp/mplus-outline-fonts/index-en.html) font by Coji Morishita (free software license).
+Embeds [stb_textedit.h](https://github.com/nothings/stb/) by Sean Barrett.
 
 Inspiration, feedback, and testing: Casey Muratori, Atman Binstock, Mikko Mononen, Emmanuel Briney, Stefan Kamoda, Anton Mikhailov, Matt Willis. Thanks!