With AppleScript 🙂 Great Idea by William Bamberg https://wiki.mozilla.org/Evangelism_Reps_Training_Program/How_to_prepare_a_screencast#Typing

More http://christianheilmann.com/2014/01/09/autmating-typing-in-screencasts-with-applescript-or-how-to-look-like-a-hollywood-hacker/

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